Korallion by Erin Burge

Korallion

Ecology of Coral Reefs Discovery Bay, Jamaica Volume I, Maymester 2010

KORALLION

Korallion

Ecology of Coral Reefs Discovery Bay, Jamaica Volume I, Maymester 2010 ii

Suggested citations for Korallion: Volume Keller JA, MR Mudron and EJ Burge, editors. 2010. Korallion. Coastal Carolina University Studies in Coral Reef Ecology. 1: 76 pp. Individual paper (example) Harmon, LR. 2010. A greater understanding of nutrient input into Discovery Bay, Jamaica through quantification of submerged groundwater discharge rates. Korallion. Coastal Carolina University Studies in Coral Reef Ecology. JA Keller, MR Mudron and EJ Burge, eds. 1: 14-20.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

FOREWORD Coastal Carolina University is a public, comprehensive university located in Conway, South Carolina, near Myrtle Beach. We are the largest undergraduate marine science program on the East Coast and one of the lead departments in CCU's Coastal Marine and Wetland Studies graduate program. With our ideal location near the coast and diverse group of research-active faculty committed to undergraduate teaching, our strength is in providing individual attention and hands-on opportunities for students. For 25 years, the Department of Marine Science has offered a study abroad course in coral reef ecology to the Discovery Bay Marine Laboratory of the University of the West Indies in Discovery Bay, Jamaica (MSCI 477 Ecology of Coral Reefs). During the nearly three-week stay in Jamaica, students are able to experience a diverse tropical marine environment first-hand through a course balanced between learning about the various ecological functions within the coral reef community, historical ecology of the reefs at Discovery Bay, and supervised development of scientific diving skills. This experience culminates with the completion of a student-initiated, facultysupervised independent research project. Each individual project is unique in subject, but all students are required to thoroughly research their topic before even arriving in Jamaica. Once all of the data has been collected and analyzed, students then compile a scientific research paper. The projects investigated during the Maymester 2010 course ranged from investigations of biota and their behaviors, to mangrove tree surveys, carbonate sediment geology, and physicochemical measurements of submerged groundwater discharge. This year is particularly special, because these papers have been edited into this volume, a first in the 25 year history of the course. This process has been frustrating at times but very rewarding. We are proud to present this journal in the hopes that it will be the first volume of many. We hope that you find these papers interesting and that they stimulate interest in our work. Cheers, Jessica Keller and Megan Mudron â&#x2DC;ş

KORALLION

TABLE OF CONTENTS Density and distribution of the long-spined sea urchin, Diadema antillarum, with respect to rugosity at Discovery Bay, Jamaica Jessica Keller........................................................... 1

Differentiation of the sea anemone Condylactis gigantea color morphs by habitat and genetics Megan Mudron ........................................................ 7

A greater understanding of nutrient input into Discovery Bay, Jamaica through quantification of submerged groundwater discharge rates Lindsay Harmon .................................................... 14

Carbonate concentration of beach sediments in Discovery Bay, Jamaica as a proxy for coastal beach erosion Ronald Cash .......................................................... 21

Marking and monitoring the growth, health and location of Acropora colonies in Discovery Bay, Jamaica John Crooks........................................................... 25

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Variation in covering response of Lytechinus variegatus due to sunlight intensity in Discovery Bay, Jamaica Jen Kisabeth .......................................................... 31

Queen conch, Strombus gigas, densities found in Discovery Bay, Jamaica Alyssa Scott........................................................... 37

The effects of Diadema antillarum on macroalgae coverage along the forereef of Discovery Bay, Jamaica Katherine Podmore................................................ 43

Analysis of sediment grain size distribution in respect to depth of coral reef grooves in Discovery Bay, Jamaica Dana Putman ......................................................... 48

Mangrove forest survey at Discovery Bay, Jamaica Amy Tyillian ......................................................... 53

Reef fish survey and biodiversity of fish in Discovery Bay, Jamaica Nick Krichten ........................................................ 58

Table of Contents

iii

KORALLION

STUDENT RESEARCHERS

Jessica Keller, Co-editor jakeller@coastal.edu Alma, Wisconsin

Ronald Cash rwcash@coastal.edu Andrews, South Carolina

Lindsay Harmon lrharmon@coastal.edu Point Pleasant, New Jersey iv

Megan Mudron, Co-editor megan.mudron@gmail.com Ocean City, Maryland

John Crooks jmcrooks@coastal.edu Arnold, Maryland

Jen Kisabeth jkkisabe@coastal.edu Bowling Green, Ohio

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Nicholas Krichten nmkricht@coastal.edu Conway, South Carolina

Katherine Podmore krpodmor@coastal.edu York, South Carolina

Alyssa Scott anscott@coastal.edu Snow Hill, Maryland

Dana Putman deputman@coastal.edu Saint Charles, Illinois

Amy Tyillian altyilli@coastal.edu Sharpsville, Pennsylvania

Student Researchers

KORALLION

INSTRUCTORS Erin J. Burge, Ph.D. Assistant Professor, Department of Marine Science Coastal Carolina University eburge@coastal.edu

Background: Dr. Burge has taught the Jamaica coral reef ecology class since 2007. His research interests include a wide range of questions relating to how marine organisms respond to environmental change, the role that human activities play in coral reef health, and tropical fish community ecology.

Erin Cziraki Graduate Student, Coastal Marine and Wetland Studies Coastal Carolina University ekczirak@coastal.edu

Research interests: Ms. Cziraki has accompanied the coral reef ecology class to Jamaica for the past two years and served last year as the primary dive safety officer. She is in the process of completing her Masters in Coastal Marine and Wetland Studies at Coastal Carolina University, where she is studying geophysics and the use of acoustic instrumentation as a means of data collection. Her thesis focuses on sediment transport processes occurring just off the beach.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Density and distribution of the long-spined sea urchin, Diadema antillarum, with respect to rugosity at Discovery Bay, Jamaica Jessica Keller Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract — The long-spined sea urchin, Diadema antillarum, is a keystone herbivore in the coral reef systems in the Caribbean. Environmental disturbances caused a mass mortality of this species in the 1980s, but there has been recovery of the population since that time. One factor that may contribute to the recovery of Diadema is the rugosity of the coral reef. In Discovery Bay, Jamaica, eleven belt transects, five perpendicular to the reef crest and six parallel, were laid on the west forereef, and the density of the Diadema, rugosity of the reef, and percent macroalgae cover were measured. Weak relationships were found between depth and Diadema density as well as between rugosity and Diadema density. The average density was found to be less than those of previous years, which may indicate a slowing of recovery rate or a spreading of the distribution of Diadema on the forereef. Keywords — Diadema antillarum, rugosity, macroalgae, Discovery Bay, Jamaica, herbivore, grazer

INTRODUCTION

throughout the Caribbean, the longspined sea urchin, Diadema antillarum, suffered a mass mortality in the mid 1980s and has yet to fully recover. In 1980, Hurricane Allen swept through the Caribbean and destroyed the shallow reef community at Discovery Bay, Jamaica. Three years later in 1983, a waterborne pathogenic disease caused a mass mortality of Diadema antillarum (Cho and Woodley 2000). This mass mortality started at the mouth of the Panama Canal, and spread by surface currents until the entire Caribbean was affected (Lessios 1988). This die-off of Diadema was the greatest mortality ever reported for a marine animal as over 93% of the Diadema population was removed (Lessios 1988). When Hurricane Allen came through the Caribbean, it destroyed much of the coral population of the reef. The loss of framework corals, including Acropora palamata and Acropora cervicornis, had significant effects as these corals provide structure for the reef as well as habitats for other reef organisms. The mass mortality of Diadema after Hurricane Allen caused many reef systems in the area to shift fm coral dominated to algae dominated. Macroalgae can slow the growth of a coral reef or even kill it by blocking the light, encroaching over live tissue, and causing abrasions (River and Edmunds 2001). Diadema is one of the main herbivorous grazers in the Caribbean reef community, and it controls benthic algae populations (Liddell and Ohlhorst 1986). Within weeks of the Diadema die-off, the macroalgal cover in the affected area increased on shallow hard bottoms (Bechtel et al. 2006). Many reefs in Jamaica had less than 5% coral cover and over 90% macroalgal cover after this event (Hughes 1994). Diadema populations began to recover in the mid NCE ABUNDANT

This research was conducted as part of the Coastal Carolina University classes MSCI 477, Ecology of Coral Reefs, and MSCI 499, Directed Undergraduate Research, in Discovery Bay, Jamaica, 12-30 May 2010.

1990s, but the rate of recovery is slow. As Diadema increases, grazing on macroalgae increases, leaving bare substrate for coral to colonize (Edmunds and Carpenter 2001). At Discovery Bay, Jamaica, previous surveys have found that the highest density of Diadema is located between 3 - 5 m deep, while below 9 m, Diadema is rare or absent (Sellers et al. 2009). Past spatial complexity data suggests that Diadema prefer complex habitat structures (Bechtel et al. 2006). A high substrate complexity, known as rugosity, provides more niches for the Diadema to take shelter in during the day. Field experiments have shown that adding physical structures, and thus enhancing spatial complexity, results in a decrease of algal cover and an increase in the proportion of urchins (Lee 2006). In a previous study, Diadema were transplanted from buttresses with high urchin densities to low urchin densities. It was discovered that the urchins not only decreased the macroalgae cover on the transplant buttresses, but they also aggregated to areas of high rugosity on the buttresses (Macia et al. 2007). The high density of Diadema between 3 - 5 m, and the lack below 9 m, may be due to the spatial complexity, or rugosity, of the reef. Since the die-off of Diadema, many surveys have been taken in the Caribbean to assess both the Diadema and macroalgae populations. Diadema has been slowly making a recovery, but recently the recovery rate has appeared to have slowed (Sellers et al. 2009). This study will continue to monitor the density and distribution of Diadema antillarum in Discovery Bay as well as measuring the rugosity of the reef both inside and outside the zone of highest Diadema density. MATERIALS AND METHODS Study sites and geographic data This study was conducted in May 2010 at Discovery Bay Marine Laboratory, which is located on the north coast of Jamaica. The study area includes three sites along the west forereef of Discovery Bay; Dancing Lady (374’N, 728’W), LTS (18 28.388’N, 77 24.833’W), and M1 (18 28.342’N, 77 24.560’W). Data collection Five belt transects, each 100 ft long (~30 m) and 2 m wide, were run perpendicular to the shore. Two perpendicular transects were run at both Dancing Lady and Mooring 1 (M1), while one transect was run at Long Term Study (LTS). Six belt transects were then run parallel to the shore with two transects at each site. Perpendicular transects were run directly north to south, while the parallel transects were run directly west to east. Parallel transects were used to obtain better data on the main density zone of Diadema. Some

Diadema antillarum in Discovery Bay, Jamaica

KORALLION 4.5 4.0 3.5 Diadema Density

transects were run above, below, and within the “Diadema zone”. The number of Diadema antillarum were counted along each belt transect, which covered approximately 61 m2. The macroalgae cover and macroalgae composition along the transect were also recorded using random quadrat sampling. The diameters of random Diadema within the belt transect were measured using calipers. The depths stated in this study were measured using a VEO 100 dive computer. The rugosity, or complexity of the reef substrate, was determined using a 15 ft chain-link line. This chain was laid along the transect line, following the benthic contours of the substrate. A Rugosity Index was established by dividing the length of the chain-link line, 15 ft, by the distance between the two ends of the chain (McClanahan and Shafir 1990). A substrate that had no contours at all, such as a sandy bottom, would have a rugosity index of 1 (15 ft chain/15 ft covered along a transect), whereas a substrate with multiple coral heads would have a higher rugosity index (15 ft/10 ft covered along a transect).

3.0 2.5 2.0 1.5 1.0 0.5 0.0 3.0

There is a weak positive relationship between density of Diadema and rugosity. In an area that was more rugose, there was a higher density of urchins. The relationship between density and rugosity was stronger for parallel transects than for perpendicular transects. The highest rugosity index was 1.92, and the lowest value was 1.02. The average rugosity index for perpendicular transects was 1.36 ± 0.28 (rugosity index ± standard deviation) and the average for the parallel transects was 1.44 ± 0.22.

4.0

4.5

5.0

5.5

6.0

6.5

Perpendicular transects

8 7 Diadema Density

R2 = 0.2159

5 4 3 2 1 0 1

Depth (m) B. Parallel transects Figure 1. Density (# of individuals/m2) of Diadema antillarum, by depth among both perpendicular and parallel belt transects. Densities were calculated by taking the total amount of Diadema found divided by the total area covered by the transect, ~61 m2.

4.5 4.0 3.5 Diadema Density

Diadema antillarum Densities by Rugosity

3.5

Depth (m) A.

RESULTS Diadema antillarum Densities by Depth The Diadema densities ranged between 0.52 m2 and 6.8m2, while the mean density between all the transects was 2.77 ± 2.02 m2. The mean density for perpendicular transects was 2.2 ± 1.74 m2 (mean density ± standard deviation). Parallel transects had a mean density of 3.17 ± 2.31 m2. The highest densities were found between 3-5 m, and the lowest density was found just below 5 m. There was not a strong relationship between Diadema density and depth, although the parallel transects did have a stronger relationship with depth compared to perpendicular transects. Parallel transects showed a slight positive relationship between density and depth, but perpendicular transects showed a slight negative relationship.

R2 = 0.3795

3.0 2.5 R2 = 0.424

2.0 1.5 1.0 0.5 0.0 1.0

1.2

1.4

1.6

Rugosity Index A.

Perpendicular transects

1.8

2.0

Diadema Density

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

R2 = 0.2409

5 4 3 2 1

0 1.0

1.2

1.4

1.6

1.8

2.0

LTS

Rugosity Index

Site

B. Parallel transects Figure 2. Density of Diadema (# of individuals/m2) with respect to rugosity indices for perpendicular and parallel transects. Diadema densities were calculated by dividing the total number of urchins counted on the belt transect by the total area of the transect (~61 m2). Mean rugosity indices are presented for each transect ± standard deviations.

Figure 4. Mean density of Diadema, expressed as # of individuals per m2 ± standard deviation, for each of the three sites in this study.

3.5

Density, Rugosity, and Size by Site The mean rugosity indices at each of the three sites were compared, and ANOVA shows that is a significant difference between the mean rugosities of LTS, M1, and DL (p = 0.0093). The average rugosity indices for these sites were 1.52 ± 0.18 (rugosity± standard deviation), 1.24 ± 0.16, and 1.48 ± 0.27 respectively. The mean densities of each site were also compared and found to be significantly different (p = 0.0202). The mean Diadema densities were: 5.20 ± 1.42 m2 at LTS, 1.48 ± 0.77 m2 at M1, and 2.25 ± 1.79m2 at DL. The mean diameter of Diadema was also compared between the three sites, and ANOVA showed that there was a significant difference (p = 0.0068). At LTS, the sampling size of the diameter measurements is as follows: LTS had 69 measurements; DL had 33, and M1 had 12. 1.8

Rugosity Index

1.7 1.6 1.5 1.4 1.3 1.2 1.1 1.0 LTS

M1 Site

Figure 3. Mean rugosity indices for each of the three sites in this study including standard deviations.

Mean Diadema Diameter (in)

3.0 2.5 2.0 1.5 1.0 0.5 0.0 LTS

Site

Figure 5. Mean diameter (in) and standard deviation of Diadema for each site.

Macroalgae Cover The density of Diadema (No. of individuals per m2) was again compared to depth, this time using the Diadema density data found by the random quadrat sampling while estimating macroalgae per cent cover. The line of best fit shows that there is no relationship between density and depth within either perpendicular or parallel transects. Density by Macroalgae Cover The densities of the urchins decreased as the per cent cover of macroalgae increased. For both the perpendicular and parallel transects weak relationships were found, with R2 values of 0.2138 and 0.3225, respectively. Macroalgae per cent cover was also looked at in relation to depth. Parallel transects showed no relationship between these two variables, but for perpendicular transects, there was a slight increase in macroalgae cover as depth increased.

Diadema antillarum in Discovery Bay, Jamaica

KORALLION 12

20 18 Diadema Density

Diadema Density

10 8 6

R = 0.0808

16 14 12 R2 = 0.3175

10 8 6 4

2 0

0 0.0

4.0

8.0

12.0

Depth (m) A.

Diadema Density

100

DISCUSSION

14 12

R2 = 0.0598

10 8 6 4 2 0 0

Depth (m) B. Parallel transects Figure 6. Density of Diadema (# of individuals/m2) by depth as found by random quadrat sampling along perpendicular and parallel transects.

10 9 8 Diadema Density

B. Parallel transects Figure 7. Density of Diadema (# of individuals/ m2) by total per cent macroalgae cover as found by random quadrat sampling along perpendicular and parallel transects.

18 16

7 6

R = 0.2095

5 4 3 2 1 0 0

Total % Macroalgae Coverage

Total % Macroalgal Coverage

Perpendicular transects

100

Diadema populations, as well as having a restricted depth zone, are very patchy on the reef. In the past, studies have looked at the Diadema densities using random quadrat sampling along a transect. However, this method does not correct for the patchiness of Diadema. In this study, belt transects were used to take a broader count of Diadema density. Even using a wider area of measurement, Diadema densities still varied greatly both between and within sites. The two types of transects run, perpendicular and parallel, showed slightly different results. When comparing Diadema densities against depth, parallel transects showed a weak positive relationship while perpendicular transects showed a weak negative relationship. While taking random quadrat estimates of macroalgae cover, the number of Diadema in the m2 quadrats were also recorded. When comparing this Diadema density data against depth, no relationship was found. This indicates that belt transects give a better representation of the Diadema population. Diadema densities were also looked at by rugosity of the reef. For both perpendicular and parallel transects, there was a positive relationship, but the parallel had a higher R2 value (0.424 vs 0.2409). The difference between transects was unexpected, but might be due to the geomorphology of the reef. The geomorphology of the reef at Discovery Bay is similar to any fringing reef, with buttresses jutting out at right angles to the reef crest (Goreau and Goreau 1973). Between these buttresses are sand channels, where debris and sediment can be funneled away from the reef. Perpendicular transects were ran along a spur, or buttress, and depth generally decreased by 1m from the shallower end to the deeper end of the transect. The mean depth along the transect was used when plotting density by depth. For parallel transects, the line ran over spurs and grooves. The substrate sometimes changed from multiple coral heads to flat, sandy areas, which would produce different rugosity indices. Three rugosity measurements were taken along the transects line, and the mean value was used when plotting rugosity. Using the mean

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 depths and rugosity indices, as well as the small sampling size, five perpendicular and six parallel transects, may inaccurately express the relationship between Diadema density and depth. Increasing the sampling size at various locations would give a better representation of the Diadema forereef population. Past studies have found that reefs in the Caribbean are becoming flatter and more structurally homogenous, with the proportion of reefs having a rugosity index greater than 2 having declined from 45% to 2% in the past four decades (Alvarez-Filip et al. 2006). In this study, the highest rugosity index was 1.92. There were no rugosity values above 2 on any of the three sites studied on the forereef of Discovery Bay. However, the substrate is not homogenous. As stated earlier, the reef has spurs and grooves, and even along a 30 m transect, there was great variation in rugosity indices. Along the transect with the highest rugosity index, 1.92, there were also rugosity values of 1.56 and 1.13. The start of a transect may have a coral dominated, rugose substrate, but 10 m later, the transect may cross a sand channel with very low rugosity. This variation in substrate complexity is likely to be a cause for why there is not a stronger relationship with Diadema density and rugosity of the reef. Surveys by divers reveal that Diadema populations are densest in areas with complex, algae-barren substrates, but the patchiness of the Diadema make measuring this occurrence difficult. To obtain rugosity indices for large areas of shallow reefs, Experimental Advance Airborne Research Lidar (EAARL), is an option for rapid assessment (Brock et al. 2006). This technique may not be suited for small studies, but would be a great indicator of the overall topographic complexity of an area During the dive surveys and measurements, Diadema were seen much shallower than in previous years. Near the reef crest, in less than five feet of water, Diadema were spotty, but in some areas very abundant. Some individuals were found deeper than 7 m, which is also outside the â&#x20AC;&#x153;Diadema Zone.â&#x20AC;? These results suggest that Diadema recovery is successful enough that the population is starting to spread out and habituate to new areas. Another unexpected result was the significant differences between sites of mean density, rugosity, and diameter of the Diadema. In all three cases, LTS had the highest mean value, while M1 had the lowest. This suggests that there is a relationship between the rugosity of an area and the density and size of Diadema. Dive surveys did not indicate that there was a difference in the size of the urchins, but physically measuring the diameters of the urchins showed that a difference did exist. A closer look at the differences between sites may be beneficial when examining the overall health of the forereef. A negative relationship was found between per cent macroalgae cover and Diadema density. For both types of transects, as macroalgae increased, the density of Diadema decreased. The relationship was again stronger for parallel transects than for the perpendicular transects, but this difference was not significant. Diadema are an important grazer in controlling macroalgae cover, but some argue that coral mortality has opened up area for algae to grow, and this algae growth may be surpassing the threshold for herbivory control (Mora 2007). There is concern that coral and

macroalgae dominated reefs are alternative stable-states, and switching back to a coral system would be difficult. However, recent studies support the view that Caribbean coral reefs are not alternative stable-states, and switching between coral and macroalgae dominated systems is a relatively simple response to environmental conditions (Idjadi 2010, Petraitis and Dudgeon 2004). It is also suggested that shifts from coral dominated to macroalgae dominated substrate is not as common or extensive as first thought (Bruno et al. 2009). Future studies on Diadema density should take into account not only the macroalgae cover, but also the rugosity of the substrate. Dive observations found that Diadema are found in areas with high rugosity indices as well as decreased amounts of macroalgae. Previous studies also suggest that rugosity is a very important factor on the overall health of coral reefs, not just for increasing urchin densities. Significant linear relationships have been discovered between rugosity and the cover of Acropora cervicornis, suggesting that topographic complexity is important for reef resilience (Crabbe 2010). High herbivory has also been associated with enhanced coral recruitment (Carpenter and Edmunds 2006, Belliveau 2002). A study on the north-east coast of the Mexican Yucatan Peninsula found a mean density of Diadema, 7.29 Âą 4.16 m2, that is much higher than those found in the Caribbean (Jordan-Garza et al. 2007). Jordan-Garza et al. also noted that the urchins were located in patches of healthy Montastraea annularis, while patches of this coral in Diadema absent areas were affects by Yellow-band and White-plague. Also, one macroalgae Diadema may graze on is Halimeda opuntia, which was found to harbor disease bacteria that cause white plague type II. Exposure to H. opuntia passes this disease to corals (Nugues et al. 2004). Diadema antillarium is an important part of the coral reef system. This idea has been studied and supported for many years. It impacts the algal and coral species on the reef, and these organisms have other, far-reaching effects. One factor that affects the density and distribution of Diadema is rusosity. A clearer understanding of the relationship between rugosity values and Diadema density distribution may aid in the recovery of this herbivore. . ACKNOWLEDGMENT The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support, Katherine Podmore and Erin Burge, Coastal Carolina University, for support and assistance throughout the entire study, and Erin Cziraki, Scientific Dive Safety Officer, Coastal Carolina University. REFERENCES Alvarez-Filip L, Dulvy NK, Gill JA, Cote IM, Watkinson AR (2009) Flattening of Caribbean coral reefs: region-wide declines in architectural complexity. Proceedings of the Royal Society 276: 3019. Bechtel J, Gayle P, Kaufman L (2006) The return of Diadema antillarum to Discovery Bay: Patterns of distribution and

Diadema antillarum in Discovery Bay, Jamaica

KORALLION abundance. Proceedings of the 10th International Coral Reef Symposium 1: 367-375.

Jordan-Garza AG, Maldonado MA, Baker DM, RodriquezMartinez RE (2007) High abundance of Diadema antillarum on a Mexican reef. Coral Reefs 27(2): 295.

Belliveau SA and Paul VJ (2002) Effects of herbivory and nutrients on the early colonization of crustose coralline and fleshy algae. Marine Ecology Program Series 232: 105-114.

Lee SC (2006) Habitat complexity and consumer-mediated positive feedbacks on a Caribbean coral reef. Oikos 112: 442 - 447.

Brock JC, Wright CW, Kuffner IB, Hernandez R, Thompson P (2006) Airborne lidar sensing of massive stony coral colonies on patch reefs in the northern Florida reef tract. Remote Sensing of Environment 104(1): 31-49.

Liddell W, Ohlhorst S (1986) Changes in community composition following the mass mortality of Diadema at Jamaica. Journal of Experimental Marine Biology and Ecology 95: 271 - 278.

Bruno JF, Sweatman H, Precht WF, Selig ER, Schutte VGW (2009) Assessing evidence of phase shifts from coral to macroalgal dominance on coral reefs. Ecology 90(6): 1478 -1484.

Macia S, Robinson MP, Nalevanko A (2007) Experimental dispersal of recovering Diadema antillarum increases grazing intensity and reduces macroalgae abundance on a coral reef. Marine Ecology Progress Series 348: 173 182.

Carpenter RC, Edmunds PJ (2006) Local and regional scale recovery of Diadema promotes recruitment of scleractinian corals. Ecology Letters 9: 271 - 280. Cho LL, Woodley JD (2000) Recovery of reefs at Discovery Bay, Jamaica and the role of Diadema antillarum. Proceedings of the 9th International Coral Reef Congress 1: 331 - 337. Crabbe, MJC (2010) Topography and spatial arrangement of reef-building corals on the fringing reefs of North Jamaica may influence their response to disturbance from bleaching. Marine Environmental Research 69(3): 158 162. Edmunds PJ, Carpenter RC (2001) Recovery of Diadema antillarum reduces macroalgal cover and increases abundance of juvenile corals on a Caribbean reef. Proceedings of the National Academy of Science 98: 5067 - 5071. Goreau TF, Goreau NI (1973) Coral Reef Project Papers in Memory of Dr. Thomas F. Goreau. 17. The ecology of Jamaican coral reefs. II. Geomorphology, Zonation, and Sedimentary Phases. Bulletin of Marine Science 23: 399 464. Hughes TP (1994) Catastrophes, phase shifts, and large-scale degradation of a Caribbean coral reef. Science 265: 1547 -1551. Idjadi JA, Haring RN, Precht WF (2010) Recovery of the sea urchin Diadema antillarum promotes scleractinian coral growth and survivorship on shallow Jamaican reefs. Marine Ecology Progress Series 403: 91 - 100. Lessios HA (1988) Mass mortality of Diadema antillarum in the Caribbean: What have we learned? Annual Review of Ecological Systems 19: 371 - 393.

McClanahan TR, Shafir, SH (1990) Causes and consequences of sea urchin abundance and diversity in Kenyan coral reef lagoons. Oecologia 83: 362 - 370. Mora C (2007) A clear human footprint in the coral reefs of the Caribbean. Proceedings of the Royal Society 275 (1636): 767 - 773. Nugues MM, Smith GW, van Hooidonk RJ, Seabra MI, Bak RPM (2004) Algal contact as a trigger for coral disease. Ecology Letters 7 (10): 919 - 923. Petraitis PS, Dudgeon SR (2004). Detection of alternative stable states in marine communities. Journal of Experimental Marine Biology and Ecology 300 (1-2): 343 -371. River G, Edmunds P (2001) Mechanisms of interaction between macroalgae and scleractinians on a coral reef in Jamaica. Journal of Experimental Marine Biology and Ecology 261: 159 - 172. Sellers AJ, Casey LO, Burge EJ, Koepfler ET (2009) Population Growth and Distribution of Diadema antillarum at Discovery Bay, Jamaica. The Open Marine Biology Journal 3: 105 - 111.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Differentiation of the sea anemone Condylactis gigantea color morphs by habitat and genetics Megan R. Mudron Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527

Abstract — Condylactis gigantea, the giant sea anemone, is a conspicuous member of the coral reef fauna in Discovery Bay, Jamaica. Individuals are located in all areas of the reef from the shallow lagoon to the deeper forereef areas, including the backreef and bay environments. Individuals also display a variety of phenotypes; most readily identifiable are the pink and green morphs. Thirteen surveys were taken of the four areas surveyed; 332 individuals were sighted and 50 tentacle tips were removed for future genetic sampling. The depth and coloration of each individual observed were recorded. Measurements of crown diameter, tentacle length, and tentacle tip width were taken of those sampled. It was observed that pink morphs were much more prevalent in the lagoon, bay, and backreef areas in comparison to green morphs. Only nine individuals, mostly green, were observed over six surveys in the forereef which could indicate that there are few individuals in this environment. These observations may indicate that pink morphs are more successful and adaptive than green morphs because they occupy a greater number of niches and are greater in number as well. Pink morphs could also prefer environments with increased turbidity. Size of individuals did not correlate with depth. Pink morphs were generally larger than green morphs, but were also more variable. It was observed that a high algal cover may correlate with higher anemone presence, and this should be investigated further in future studies. Future genetic testing will take place at Coastal Carolina University. Keywords — Condylactis gigantea, color morphs, genetic variation, reef habitat

INTRODUCTION

are diverse communities and the habitat is influenced by both abiotic and biotic factors, especially by the amount of light received (Brown 1997). These factors determine spatial variation (i.e. depth) among organisms, including anthozoans that require endosymbiotic photosynthesis by zooxanthellae and therefore must be in direct sunlight (Chalker and Taylor 1978). The transmission of light through water is affected by depth and turbidity. It has been found that color of an organism differs with depth and habitat type, including the sea urchin Paracentrotus gaimardi (Calderon et al 2010), Great Star Coral Montastraea cavernosa (Field et al 2006; Kelmanson and Matz 2003), Brain Coral, Lobophyllia hemprichii, Elegance Coral, Catalaphyllia jardenei (Oswald et al 2007), and Giant Sea Anemone Condylactis gigantea (Stoletzki and Schierwater 2005), as well as other reef-building coral species (Dove et al 2001). Anthozoans, including corals, obtain pigmentation ORAL REEFS

through a specific sequence of GFP-like proteins (Kelmanson and Matz 2003). It has been hypothesized that various colors of GFP-like proteins evolved as a regulatory mechanism between coral and its endosymbionts. During photosynthesis by zooxanthellae, light wavelengths are subtly modified and different color morphs receive varying amounts of light (Field et al 2006). Major gene linkages in Montastrea cavernosa have differentiated over time in response to environmental changes to produce cyan, green and red color morphs. Differences arose from the varying levels of gene expression (Kelmanson and Matz 2003).

A. C. gigantea- Pink morph

B. C.gigantea- Green morph

Figure 1. These two photographs illustrate the difference between color morphs of the sea anemone, Condylactis gigantea.

Different color morphs may be present due to organism diet (Tlusky and Hylad 2005), behavioral patterns (Pryke 2007), age (Medioni et al 2001), or variances in gene expression (Kelmanson and Matz 2003). Color difference with depth may also be correlated to UV radiation levels, especially in tropical areas where radiation is high (Gleason 1993; Hoegh-Guldberg 1995; Stoletzki and Schierwater 2005). Pink and green morphs of the Giant Sea Anemone Condylactis gigantea (Figure 1) have been observed in Discovery Bay, Jamaica. More pink morphs have been found in deeper habitats of the lagoon with less light. In comparison, more green morphs have been found in clearer water and in less than 10 m of water in the forereef (Stoletzki and Schierwater 2005). In their natural habitat, green morphs of C. gigantea absorbed significantly less UV-B and more UV-A radiation regardless of depth. After transplantation to a new habitat, green morphs of C. gigantea were found to absorb more UV-B and less UV-A radiation at 1 m than pink morphs and the opposite was true at 15 m. The absorption rates of both colors were low at 18 m (Stoletzki and Schierwater 2005). Mycosporine-like amino acids (MAAs) may be present to offer protection against UV radiation to anthozoans, where varying MAA concentrations may link different colors with physiological performance (Gleason 1993). The composition of MAA’s in C. gigantea

Condylactis gigantea in Discovery Bay, Jamaica

KORALLION

have been found to differ with depth (Dunlap and Shick 1998, 2002; Stoletzki and Schierwater 2005). Various color morphs may have adaptive significance as a response to light variance. Color was not found to be associated as a photoprotectant, fluorescent coupling agent, or a UV screen in pocilloporid and acroporid corals (Dove et al 1995). In the sea urchin Paracentrotus giamardi there were no morphological, diet, light, or wave exposure differences other than a color difference between morphs. In addition, color was not directly involved in mate choice (Calderon et al 2010). Even though these results have been found for other anthozoan species, they are not necessarily true for C. gigantea. Past studies on this species suggest that different color morphs are probably adaptively significant and that gene flow is differentiated even in overlapping habitat (Stoletzki and Schierwater 2005). Regardless of the ecological importance, it stands that these colors have mutated from an original ancestor and persisted into the present; therefore color may influence overall organism fitness (Field et al 2006). Within the aqueous world, sexually reproductive organisms are differentiated through natural selection and gene flow (Ayre and Hughes 2000; Slatkin 1973). Anthozoans, including C. gigantea, have a large range of dispersal with few extrinsic barriers (Bohonak 1999). This generally leads to low genetic differentiation over the entire area (Palumbi 1994). However, in Discovery Bay, pink and green morphs both occupy the same habitats, yet there is low gene flow between colors morphs (Stolezki and Schierwater 2005). There is significant genetic difference between color morphs in the lagoon and forereef populations. While no association was shown between color and ITS variant in the forereef, a strong association between variables- as much as two different species- was found in the lagoon. (Stoletzki and Schierwater 2005).

MATERIALS AND METHODS Study Area The study took place at the Discovery Bay Marine Laboratory (DBML), located on the north coast of Jamaica. Four environments of the coral reef were studied: the forereef, backreef, bay, and lagoon. (Figure 2). The forereef is highly influenced by storms since there is little protection, and there is high wave action. At this site, the water is clear and light levels are high. The backreef is similar to the forereef but hard substrate is located within a shallower depth. The lagoon is a more protected habitat than the forereef so it is less impacted by waves. The water is turbid and thus light levels are lower (Gayle and Woodley, 1998). The bay is also turbid and is a similar environment to the lagoon except it is deeper. Landderived sediment deposition impacts the bay and lagoon at a higher rate than the forereef. There is a higher algal cover in the lagoon and bay environments than in the forereef environment.

Over varying environmental factors like depth, there can be high rates of phenotypic variation which may indicate phenotypic plasticity or genetic polymorphism (Bruno and Edmunds 1997). With increasing genetic diversity, anthozoans are less susceptible to global warming threats like coral bleaching (Ayre and Hughes 2004). These traits likely have adaptive significance that increases the overall fitness of C. gigantea. C. gigantea can be found at depths between 1 to 33 m in varying habitat types of the Caribbean (Humann and DeLoach, 2002). Endosymbiotic dinoflagellates of the genus Symbiodinium are associated with C. gigantea (Banaszak et al. 1993, 2006). These endosymbionts are golden-brown (Dove et al 2001) but there is no correlation of symbiont color with host color in the giant sea anemone (Stoletzki and Schierwater 2005). However, in Montastraea cavernosa, the pigments of zooxanthellae strongly affect color of the coral. These pigments are light dependent (Oswald et al 2007). While the color morphs of C. gigantea have been studied in the past with respect to habitat type, no study to date can explicitly state why they are ecologically significant. Overall, the speciesâ&#x20AC;&#x2122; distribution remains largely unstudied, even though the organism is a conspicuous member of the reef fauna. The purpose of this investigation is to expand the geographic boundaries of the study in Discovery Bay and to add additional variables besides depth, which may give further insight into the genetic differences between morphs when analyzed. The surrounding habitat and substrate of the anemones, anemone size, other organisms present, and the anemone color (pink, green, or other colors) will be obtained and analyzed. Through the accumulation of this data, the adaptive significance of the different color morphs should be better understood at the conclusion of this project.

Forereef Backreef Bay

Figure 2. An aerial photograph of Discovery Bay, Jamaica, detailing the forereef, backreef, and lagoon locations within the bay.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Statistical Analysis Significance between the numbers of pink morphs observed during surveys in comparison to green morphs observed was determined using a one-tailed t-test. Correlation between size measurements of individuals and how these sizes varied with depth were determined through a linear regression test. RESULTS Throughout thirteen surveys, 332 Condylactis gigantea individuals were observed and 50 representatives were sampled for genetic testing (Table 1). Only surveys in which individuals were sighted were tabulated; two forereef surveys were not included and two additional surveys were combined as they were in overlapping depths and locations. C. gigantea was easily distinguished with either pink or green coloration. Two additional morphs were also identified- a pink and green morph hybrid and a morph that seemed to have no distinct coloration at all. For the purpose of this study, only pink and green morph variation was analyzed so that comparison with Stoletzki and Shierwater (2005) is possible. C. gigantea was most commonly observed in the lagoon and the bay environments (see Figure 3). Individuals were slightly less frequently seen in the backreef sites and were rarely seen in any of the three forereef sites. Pink morphs were most commonly viewed in all areas of the lagoon, bay and backreef. There was 84.4% coverage of pink morphs in the lagoon in 0.6-1.2 m, 82.8% pink morphs in the shallower depths of the bay from 2.4-4.5 m, and 81.3% pink morphs in the deeper

70 60 Number Observed per Survey

Data Collection Thirteen visual surveys to determine C. gigantea presence were conducted over hard substrate surfaces at depths up to 21.3 m in the west forereef, the east backreef, the lagoon, and in several locations in the bay. The color and depth range were recorded. Determination of coloration was aided by the presence of a light if anemone was located at depths below 15 m. The surrounding habitat and substrate and other organisms present on the anemone were recorded. One 3 cm long tentacle tip of an anemone representative of the population was removed with scissors at all depths. Depth, coloration and width of the tentacle tips, average length of the tentacle, and crown diameter were recorded for each anemone sampled. Tentacles were randomly measured. Photographs were taken of each anemone sampled using a 6 megapixel Intova IC600 underwater digital camera. Several anemones of each color were sampled at varying depths in each location. Tentacle samples were stored in seawater for the duration of the dive, and then transferred into an ethanol storage buffer solution at DBML and stored in a freezer. Genetic testing will take place at Coastal Carolina University at a later date, following the methods described in Stoletski and Schierwater (2005).

50 40 30 20 10 0 Forereef Backreef Blue Hole

Dorm Shore

Lagoon

Location Figure 3. The amount of C. gigantea pink and green morphs observed per survey in each of the environments surveyed. The most individuals were observed in the lagoon and the least individuals were observed in the forereef in a single survey. Table 1. Number of pink and green C. gigantea color morphs according to depth observed in various locations. Location Depth Range (ft) Pink Green 2-4 65 12 Lagoon Bay 8-15 48 10 Forereef 16 2 0 Bay 15-25 39 4 Bay 21-28 61 19 Forereef 15-35 1 5 Backreef 20-30 50 15 Forereef 70 0 1

depths of the bay from 4.6 - 8.5 m. In the backreef, there was 76.8% coverage of pink morphs from 6 - 9 m. In all areas behind the reef crest (i.e. the backreef, bay and lagoon environments), there was a significant difference (p = 0.0068) in the number of pink morphs in comparison to green (see Figure 4). In the forereef though, green morphs were twice as prevalent as pink morphs among the nine individuals observed but this difference was not found to be significant (p = 0.182). In all other surveys, there were enough individuals (over 40) to determine a representative color scheme of the population. A single green morph was observed at 21 m at the forereef; however that single individual is probably representative of others that inhabit the same depth but were not observed. C. gigantea size, based upon crown diameter, tentacle length, or tentacle tip width, did not seem to be correlated with depth. However, crown diameter generally increased with increasing tentacle length (pink: r = 0.92, green: r = 0.42). Tentacle tip width did not seem to be correlated with either of the other two measurements. Pink morphs were generally larger than green morphs. The average pink morph had a crown diameter of 7.5 cm, tentacle length of 6 cm, and tentacle tip width of 4.4 mm. The average green morph had a crown diameter of 6.4 cm, tentacle length of 4.7, and tentacle tip width of 3.3 mm. While pink morphs were generally bigger

Condylactis gigantea in Discovery Bay, Jamaica

KORALLION

Pink Green

120

Number Observed

Pink Green

100

50 40 30 20

60 40

10 20

0 0

2-4

8-15

Depth Range (ft)

C) 60

16-28 Depth Range (ft)

D) 2.5

Pink

2 Number Observed

Number Observed

Green

50 40

30 20

1.5

0.5

20-30 Depth Range (ft)

25 30 Depth Range (ft)

Figure 4. The number of pink morphs observed compared to green morphs for each of the locations surveyed (A = lagoon, B = bay, C = backreef, D = forereef). In the lagoon, bay, and backreef environments, there were significantly more pink morphs than green morphs. In the forereef, there were twice as many green morphs as pink morphs.

seemed that C. gigantea was more prevalent in areas of higher algal cover (i.e. the lagoon). Average-Pink

Average-Green

10 8 Size

in size, individuals were also more variable in size. Several pink morphs had average tentacle tip widths of up to 12 mm. No green morphs were observed with tentacle tip widths larger than 5 mm. Individual C. gigantea were observed only on hard substrate surfaces and never in seagrass beds or sand. While individuals were mostly seen around coral structures, several were observed on artificial piping or on rocks and rubble. Several crustaceans were observed on the anemone, including Mithrax cinctimanus and Stenorhyncus seticornis. Three individual mutations were observed during surveys and were sampled for genetic testing. Two of these mutations were individuals with Y-shaped tentacles; both individuals were located in the backreef. The third mutation was a unique coloration of the tentacle tips, where at least seven of the tentacles were half pink and half green (rather than a single color); this observation took place in the lagoon. In addition, it was noticed that individuals were not often seen in locations that had a high coral cover (i.e. the forereef); instead it

6 4 2 0 Tentacle Tip Width (mm)

Tentacle Length (cm) Crown Diameter (cm) M easurement

Figure 5. The size of pink and green C. gigantea morphs. Pink morphs were generally larger than green morphs.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 DISCUSSION Condylactis gigantea variation A significant spatial variation between pink and green morphs of Condylactis gigantea was observed in the lagoon, bay, and backreef environments of Discovery Bay, Jamaica. Pink morphs were much more prevalent in all of these areas, regardless of depth. While in prior studies pink morphs were more prevalent in the lagoon at deeper depths and green morphs were found in the forereef and other brighter locations at a shallower depth (Stoletzki and Schierwater 2005), the number of pink morphs in the lagoon, bay, or backreef environments and the number of green morphs in the forereef, while limited, did not seem to be influenced by depth. The addition of the backreef and bay environments to the area surveyed may give greater insight to the distribution of pink morphs and may indicate that their presence is actually not limited by depth as previously indicated. The low number of forereef observations showed that few individuals were located in the forereef regardless of color, even though they were observed over six normal-length dives. Pink morphs may be capable of more extensive adaptation to new niches than green morphs since they are more prevalent in several different environments. Higher prevalence may also suggest that pink morphs have a greater fitness than green morphs. In the prior study, a numerical prevalence in each area was not discussed so comparison of this variable is not directly applicable (Stoletzki and Schierwater 2005). However, due to low observance of individuals in the forereef sites, conclusions as to their correlation with depth can not be determined without additional observance in the future. The observation that more individuals were found in the lagoon, bay and backreef areas than in the forereef may suggest that higher C. gigantea presence is correlated with higher turbidity levels and lower light levels, especially for pink morphs (Gayle and Woodley 1998). This observation may also be correlated with the observation that more algae were present in the lagoon and bay areas than in the forereef. It seemed that C. gigantea presence increased with increasing algal presence, and it would be interesting in future studies to determine this correlation, if one is present. In this case, it could be possible that C. gigantea is a poor competitor for available resources, such as space, in comparison to coral species, as could be potentially observed on the forereef. In a similar species, Stichodactyla gigantea, individuals are found in similar environments that consist of hard rock substrate, shallow sandy bottoms, and sparse seagrass beds. This species seemed to be less prevalent in areas of high coral concentration (Hattori and Kobayashi 2008). Measurements of C. gigantea indicated that crown diameter increased with increasing tentacle size, which intuitively makes sense. Tentacle tip width was not correlated with either of the other two measurements, and none of the measurements correlated with depth. This indicates that all sizes of individuals are possible regardless of depth. This result is consistent to a similar study of Stichodactyla gigantea where the size of an individual didnâ&#x20AC;&#x2122;t correlate with depth either (Hattori and Kobayashi 2008). However, in the

study anemones were generally bigger in the coral patch areas and it was suggested that patch reefs are the most suitable habitat for individuals and so they grow larger, supporting the optimal body size theory. As stated, sufficient evidence for this trend is not available in the current study due to low sample size, but future studies could investigate this theory further. Tentacle tip width ranged from 2 - 12 mm, and larger widths were only seen in the pink morphs. This may be an adaptation to deal with UV absorption, and it will be interesting to see how the various tentacle tip widths are related to each other when the genetic tests are analyzed. In prior studies, color morph difference with depth has been correlated with UV absorption (Gleason 1993; HoeghGuldberg 1995) since individuals at various depths receive different amounts of light (Field et al 2006). MAA presence could be linked with protection from UV radiation and varying MAA concentrations may affect individual color morph due to various physiological performances (Gleason et al 1993). The composition of MAA in C. gigantea have been found to differ with depth (Dunlap and Shick 1998; 2002) which is likely the source of individual color differences. Pink morphs may also be able to adapt into a greater amount of habitats based on their larger size variation. Additional adaptations to UV absorption may be linked with the three mutations observed- 2 Y-shaped tentacles on pink morphs and a single morph with half green and half pink tentacles rather than a single color. These mutations may also be a result of land-based pollution, as both locations were within 50 m of land that was influenced by humans through construction of buildings. Expected Future Results Genetic testing at a future date should indicate a difference between pink and green morphs in addition to their habitat selection. In prior studies, it was suggested that color differences in depth may be related to UV absorption and radiation as it affects MAA concentrations which are adaptively significant as a photoprotectant (Gleason 1993; Takabayashi and Hoegh-Guldberg 1995; Stoletzki and Schierwater 2005). Also, color morphs may select for the same color during mating, even though there arenâ&#x20AC;&#x2122;t distinct barriers between gametes, which would eventually result in separate species (Palumbi 1994; Stoletzki and Schierwater 2005). It will be interesting to determine whether pink and green morphs display the same level of relatedness as in the prior study or if there is a different amount of relatedness between the two additional locations, the bay and backreef environments. It is likely there will be a distinct genetic variance between pink and green morphs since this occurred in the past study (Stoletzki and Schierwater 2005). As of yet, the exact adaptive significance is still unclear, but after the genetic tests are run, a better understanding of Condylactis gigantea and its adaptations should be determined. ACKNOWLEDGMENT The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. In addition, Lindsay Harmon, Dana Putman,

Condylactis gigantea in Discovery Bay, Jamaica

KORALLION John Crooks, and Nick Krichten deserve recognition for their help in collecting samples in the field, and Dr. Erin Burge for his recommendations and support. REFERENCES Ayre DJ, Hughes TP (2000) Genotypic diversity and gene flow in brooding and spawning corals along the Great Barrier Reef, Australia. Evolution. 54: 1590-1605. Ayre DJ, Hughes, TP (2004) Climate change, genotypic diversity, and gene flow in reef-building corals. Ecology Letters. 7: 273-278. Banaszak AT, Iglesias-Prieto R, Trench RK (1993) Scripsiella velella sp. nov. (Peridinales) and Gloeodinium viscum sp. nov. dinoflagellate symbionts of two hydrozoans (Cnidaria). Journal of Phycology. 29:517– 528. Bohonak AJ (1999) Dispersal, gene flow and population structure. Quarterly Review of Biology. 74:21–45. Brown BE (1997) Coral Bleaching: Causes Consequences. Coral Reefs. 16: S129-138.

and

Bruno JF, Edmunds PJ (1997) Clonal variation for phenotypic plasticity in the coral Madracis mirabilis. Ecology. 78: 2177-2190. Calderon I, Ventura CRR, Turon X, Lessioss HA (2010) Genetic divergente and assortive mating between colour morphs of the sea urchin Paracentrotus giamardi. Molecular Ecology. 19: 484-493. Chalker BE, Taylor DL (1978) Rhythmic variations in calcification and photosynthesis associated with the coral Acropora cervicornis. Proceedings of the Royal Society. 201: 179-189 Dove SG, Takabayashi M, Hoegh-Guldberg O (1995) Isolation and Partial Characterization of the Pink and Blue Pigments of Pocilloporid and Acroporid Corals. Biology Bulletin. 189: 288-297. Dove SG, Hoegh-Guldberg O, Ranganathan S (2001) Major colour paterns of reef-building corals are due to a family of GFP-like proteins. Coral Reefs. 19: 197-204. Dunlap WC, Shick JM (1998) Ultraviolet radiation-absorbing Mycosporine-like amino acids in coral reef organisms: A biochemical and environmental perspective. Journal of Phycology. 34: 418-430. Dunlap WC and Shick JM (2002) Mycosporine-like Amino Acids and Related Gadusols: Biosynthesis, Accumulation, and UV-Protective Functions in Aquatic Organisms. Annual Review of Physiology. 64: 223-262. Field SF, Bulina MY, Kelmanson IV, Beilawski JP, Matz MV (2006) Adaptive evolution of multicolored fluorescent 12

proteins in reef-building corals. Journal of Molecular Ecology. 62: 332-339. Gayle PMH, Woodley JD (1998) Discovery Bay, Jamaica. In: Kjerfve B (ed) CARICOMP Caribbean coral reef, seagrass and mangrove sites. Coastal region and small island papers. 3. UNESCO, Paris. Gleason DF (1993) Differential effects of ultraviolet radiation ongreen and brown morphs of the Caribbean coral Porites asteroides. Limnology Oceanography. 38:1452– 1463. Humann P and DeLoach N (2002) Reef creatures. New World, Jacksonville, Fla. 2: 91. Hattori A and Kobayashi M (2008) Incorporating fine-scale seascape composition in an assessment of habitat quality for the giant sea anemone Stichodactlya gigantea in a coral reef shore zone. Ecological Research. 24: 415-422. Kelmanson IV, Matz MV (2003) Molecular Basis and Evolutionary Origins of Color Diversity in Great Star Coral Montastraea cavernosa. Molecular Biology Evolution. 20(7): 1125-1133. Medioni E, LeComte Finiger R, Louviero N, Planes S (2001) Genetic and demographic variation among colour morphs of cabrilla sea bass. Journal of Fish Biology. 58: 11131124. Oswald F, Schmitt F, Leutenegger A, Ivanchenko S, D’Angelo C, Salih A, Maslakova S, Bulina M, Schirmbeck R, Neinhaus GU, Matz MV, Weidenmann J (2007) Contributions of host and symbiont pigments to the coloration of reef corals. FEBS Journal. 274: 11021109. Palumbi SR. (1994) Genetic divergence, reproductive isolation, and marine speciation. Annual Review of Ecological Systems. 25:547–572. Pryke SR and Griffith SC (2007) The relative role of male vs. female mate choice in maintaining assortative pairing among discrete colour morphs. Journal of Evolutionary Biology. 1512-152. Shick, JM, Dunlap, WC (2002) Mycosporine-like amino acids and related gradusols: biosnythesis, accumulation, and UV-protective functions in aquatic organisms. Annual Review of Physiology. 64: 223-262. Slatkin, M (1973) Gene flow and selection in a cline. Genetics. 75: 733-756. Stoletzki N, Schierwater B (2005) Genetic and color morph differentiation in the Caribbean sea anemone Condylactis gigantea. Marine Biology. Springer Science & Business Media B.V. 747-754.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 Takabayashi M, Hoegh-Guldberg O (1995) Ecological and physiological differences between two colour morphs of the coral Pocillopora damicornis. Marine Biology. 123:705â&#x20AC;&#x201C;714. Tlusty M and Hyland C (2005) Astaxanthin deposition in the cuticle of juvenile American lobster (Homarus americanus): implications for phenotypic and genotypic coloration. Marine Biology. 147: 113-119.

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A greater understanding of nutrient input into Discovery Bay, Jamaica through quantification of submerged groundwater discharge rates Lindsay Harmon Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract — Although the bottom-up or nutrient control hypothesis explaining the recent phase shift of Discovery Bay, Jamaica from coral dominated to algal dominated does not appear to be accurate, it has been proved that nutrients still play an important role in the community structure. This study was conducted in May 2010 and was designed to obtain values of submerged groundwater discharge (SGD) for an understanding of its spatial and temporal variations and thus nutrient enrichment rates of the bay. SGD did not appear to respond to daily tidal height variations but did suggest a response to the lunar tidal cycle. Data was obtained for five days, and thus the sample size is not large enough to conclude anything definitively. It is recommended that future studies measure discharge over multiple tidal cycles. Keywords — Submerged groundwater discharge,

Discovery Bay, Jamaica, nutrients

INTRODUCTION

UBMERGED GROUNDWATER DISCHARGE (SGD) is a significant mechanism for transporting inland water and dissolved materials to the coast. In the tropical coastal environment of a coral reef, the low nutrient levels typically associated create an opportunity for the introduction of low saline high nutrient groundwater to cause significant effects. In particular, elevated levels of nitrate and phosphate can increase productivity and in high enough concentrations cause eutrophication (D’Elia 1981). Until 1987 when a seepage meter was used to measure discharge rates, only the concentration of nutrients was measured on coral reefs (Lewis 1987). Since then, SGD has been quantified using tracers, piezometers, water balance calculations and modeling. Though of those, a seepage meter is the only way to measure SGD directly (Taniguchi et al. 2003). The SGD into the tropical coastal habitat located in Discovery Bay, Jamaica, West Indies, remains a mystery in most areas because it is usually unseen and difficult to measure. As of 2003, SGD had only been measured at approximately 100 sites world-wide (Bokuniewicz 2003). This is because ground water seepage is patchy, diffuse, temporally variable, and may involve multiple aquifers (Burnett et al. 2006). Although no discharges rates have been obtained for the area, extensive research has been conducted on the nutrient concentrations entering the system by submerged springs. The environment is located on the north central coast of the island and is partially enclosed and protected from the open ocean by

a fringing reef extending two-thirds across the bay. The basin is roughly 1.4 km2 in area, has a maximum depth of 50 m, a 15 - 60 cm tidal range, and experiences a slow east to west current. The limestone hard bottom that comprises the bay has been extensively fractured and eroded causing cracks that allow the terrestrial water to be channeled sub-aerially to the bay (D’Elia 1981; Bonem 1988). Since there are no rivers flowing into the bay, the only way these terrestrial nutrients enter the bay is through such submerged springs or groundwater runoff. The high productivity and biodiversity found at Discovery Bay is uncharacteristic for such shallow marine environments. Attempts to understand this abnormality have been approached by D’Elia (1981), Kramer (2009), Folger (2008), Renchen (2008) and others whose studies analyzed the nutrients found throughout the bay. These studies found that in Discovery Bay there were high concentrations of nitrate throughout with especially high values near submerged springs. A strong negative correlation between nitrate and salinity, temperature and dissolved oxygen illustrated this trend. Contrastingly, phosphate, nitrite, and ammonia showed no significant correlation. This is supported by Johannes and Hearns (1985) who observed that submerged groundwater sites have higher concentrations of nitrogen compared to phosphorus. Discovery Bay was once considered a coral dominated habitat but has undergone a phase shift to a macroalgae dominated habitat as of 1980 (Kramer 2009). Macroalgae are typically in low abundance because of low nutrient availability and grazing from fish and invertebrate predators (Lapointe et al. 1997). In an attempt to explain the phase shift three main hypotheses have arose. The first and most accepted is the topdown explanation in which the mass mortality of the benthic grazer Diadema anitllarun allowed the macroalgae percent cover to increase (Woodley et al. 1981; Hughes 1994). The second explanation states that the increase in nutrient input into coastal waters via anthropogenic sources led to the eutrophication of the water causing the macroalgae to flourish (LaPointe 1997). Lastly the third explanation referred to as the relative dominance model suggests that the phase shift took place due to a combination of both reduced herbivory and increased nutrient concentrations. In a low nutrient concentration and high grazing environment, corals predominate; while in high nutrient and low grazing environments, macroalgae takes over (Littler and Littler 1985). Recent work conducted in Discovery Bay (Folger 2008; Szmant 2002; Greenway 2006; Kramer 2009) indicates that

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. the increased nutrient levels could not be the sole driver of the phase shift. Regression tests comparing macroalae percent cover to distance from the spring showed no significance between the two. The low phosphate concentrations found in the groundwater disproves the eutrophication hypothesis, and the decline in macroalgae cover in 1998 - 1999 would have resulted in a sudden decline of groundwater into the bay, but there was no decline in rainfall at that time (Aronson and Precht 2000). This does not rule out rule out that nutrients play a secondary role. Kramer (2009) found evidence suggesting that nutrients are still involved by selecting the species of macroalgae able to be present. Nutrients have been found to indirectly contribute to community structure shifts, especially when couple with reduced herbivory or decreased topographic complexity from storms (Szmant 2002). This explanation describes Discovery Bay’s recent history of two major Hurricanes since the 1980s and the mass mortality of Diadema antillarum. An understanding of how and when nutrient enrichment will affect the declining reef system of Discovery Bay requires analysis of all mechanisms involved in nutrient dynamics (Szmant 2002). That is why more concrete conclusions can not be made until the discharge rate of the springs has been quantified, providing a better understanding of amount of nutrients entering the system over a period of time (D’Elia 1981). The purpose of this study is to provide the data needed to assess the nutrients role in the recent phase shift by quantifying the SGD rates into Discovery Bay. MATERIALS AND METHODS Surveys were conducted from May 21-26, 2010 within the western fore reef of Discovery Bay, Jamaica. This site was chosen because extensive nutrient sampling had been done previously. Jamaica usually experiences a mixed tidal range, with primarily diurnal spring tides, and low amplitude diurnal neaps. Two different springs were analyzed within the western portion of the bay in an attempt to quantify the average rates at which nutrient rich terrestrial water was discharged into the bay. Based on a salinity contour map of Discovery Bay constructed by Kramer (2009) the dominant heads of each spring were determined and used as the points where the velocity was measured. The first spring referred to as White Pole Spring had three main heads measured and the second spring referred to as East Jetty Spring had one. Velocity measurements were obtained using a Marsh-McBirney portable current meter. The current meter measured velocity in the vertical direction (z) from an electromagnetic sensor within the ranges of 0 to 6.10 m/s. The meter’s sensor was held above each head for two minutes, allowing for an initial 30 second stabilization period and three subsequent velocity were plugged into Equation 1, as the spring heads were associated with an ellipse shape. (1)

Measurements were taken in the early morning, late morning, and for two days also in mid afternoon for a six-day period approaching Spring Tide. The times of collection were based as closely as possible around high and low tides. The discharge was then calculated for each time of collection using Equation 2: 2

(2) Discharge (Q) m3/s = Velocity (z) m/s * Area (A)

m /s The three velocities were averaged together for a final velocity of that head for that collection time. To obtain the area for which the groundwater discharged from, the dimensions of the deepest point visible of each head. A salinity map of the springs at depth was conducted using a YSI conductivity meter. A 20 ft transect line was placed in North, South, East and West directions from the center of the spring for Spring 2, and from the middle point between all three heads for Spring 1. Salinity measurements were taken at every one ft interval in each direction right above the bottom. For Spring 2, the YSI cable was not long enough, so the salinity measurements were taken from 0.5 meters above the bottom. RESULTS Both springs were located within the western portion of the bay directly in front of the Discovery Bay Marine Laboratory. White Pole spring is located directly north of the boat docks and slightly west of the second red channel marker. The spring discharge is mainly from three heads located at two meters depth. It is important to note that there were multiple fissures in the limestone hard bottom within the surrounding area that groundwater was visibly seeping out of. East Jetty Spring was located slightly north east of the jetty and was approximately three meters deep. At each spring, velocity measurements were taken on May 21, May 22, May 23, May 25, and May 26, 2010. White Pole Spring Discharge Daily discharge rates ranged from 70,000 - 96,000 m3/day. Of the 5 days worth of measurements, days 3 and 4, 2 and 4, 1 and 3, and 3 and 5 were statistically different. In sequential order, a difference between daily discharge rates was only observed between May 23 and May 25 (Figure 1). On May 21 velocity measurements were recorded at 7:00am, 10:30am, and 2:00pm. On May 22, measurements were taken at 7:00am and 11:30am. For May 23, at 7:00am and 2:00pm, May 25 at 7:00am and 11:30am, and finally May 26 at 7:00am and 10:30am (Figure 2). For each day, the statistical significance between hourly discharge relative to high and low tides was not able to be obtained using a three way ANOVA sequence

Area = pi(a)(b)

Nutrient input through submerged groundwater discharge

KORALLION

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. d)

Figure 1. Average hourly discharge rates from White Pole Spring and East Jetty Spring. The discharge rates are displayed by the hour in which they were collected. The data does not appear to exhibit any trend in respect to daily tidal height variation but does show a slight response to tidal amplitude in respect to the lunar tidal cycle. The validity of this trend is limited by the lack of statistical significance. a) May 21, 2010 b) May 22, 2010 c) May 23, 2010 d) May 25, 2010 e) May 26, 2010.

because of the varying collections times. The data does not vary but does show a slight response to tidal amplitude in respect to the lunar tidal cycle. The validity of this trend again is limited by the lack of statistical significance. East Jetty Spring Discharge Daily discharge rates ranged from 18,000 to 26,500 m3/day. Throughout the collection period none of the discharge measurements were found to be significantly different (Figure1). On May 21 velocity measurements were recorded at 10:30am and 2:00pm. On May 22, measurements were taken at 7:00am and 11:30am. For May 23, at 7:00am and 2:00pm, May 25 at 7:00am and 11:30am, and finally May 26 at 7:00am and 10:30am (Figure 2). As with the White Pole Spring, the significant difference between hourly discharges was unable to be obtained. The data, however did not appear to suggest any response to the varying tidal heights.

White Pole Spring Salinity Heads 1 and 2 were seen along the North-South transect and were approximately 6 meters apart (Figure 3), while Heads 1 and 3 were seen on the East-West transect roughly 3 meters apart (Figure 4). Both the North-South and East-West transect lines illustrated a stable salinity around 34.5 ppt until directly over the spring when the salinity would drop to between 27.3 and 29.7 ppt for approximately 1 - 2 ft. East Jetty Salinity The salinity range was smaller that White Pole Spring measuring between 30.5 and 34.5 ppt. There was great variation along each transect. In the East-West transect, salinities remained low beyond the spring head in the western direction for approximately 5 ft until it began to steadily increase back to the ambient seawater salinity of about 34.4 ppt. In the North-South transect, salinities to the South were extremely stable around 34.0 while salinities to the North showed fluctuation between 32.8 and 34.4 ppt.

Nutrient input through submerged groundwater discharge

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Figure 2. Average daily discharge rates for both White Pole Spring and East Jetty Spring. White Pole Spring shows only one statistically significant change in outflow from one day to the next between May 23 and May 25. East Jetty Spring shows no significant variation throughout.

Figure 3. Salinity measurements taken every 1 foot along a North to South transect line of White Pole Spring. Negative numbers indicate movements to the North, while positive numbers represent movements to the South.

Figure 4. Salinity measurements taken every 1foot along a West to East transect line of White Pole Spring. Negative numbers indicate movements toward the West while positive numbers represent movements to the East.

Figure 5. Salinity measurements taken every 1 foot along a North to South transect line of East Jetty Spring. Negative numbers indicate movements to the North while positive numbers represent movements to the South.

Figure 6. Salinity measurements taken every 1 foot along a West to East transect line of East Jetty Spring. Negative numbers indicate movements to the West while positive numbers represent movements to the East.

DISCUSSION The significant difference in discharge between May 23 and May 25 seen in the White Pole Spring may be due to the heavy rain received on May 21. Greenway (2006) noted that when measuring salinity concentrations from submerged springs in Discovery Bay, a salinity reduction was observed 1 to 5 days after a rain event. Other studies in the bay found that the salinity response was seen 2 days after the rain (Renchen 2008). Capone and Slater (1990) noted that water table height could determine the groundwater outflow rates. The stable discharge rates observed from East Jetty Spring is unusual. In all studies cited, fluctuations in salinity, nutrients, and groundwater discharge were seen on short times scales (days). The lack of variation seen here may be explained by the small sample size. Having only 5 days worth of data provides little insight into the overall picture. The absence of discharge response to tidal height at both springs is in agreement with Giblin and Gaines (1990) and Cable et al. (1997b). However, it is opposing to what has been seen by Lee (1997), Lewis (1987), Robinson et al. (1998), and Taniguchi (2003) (Andersen 2006). Taniguchi (2003) conducted various studies in the Gulf of Mexico quantifying groundwater discharge and found that dominant change in discharge was seen in 12 hour intervals suggesting a major tidal forcing. The absence in tidal variation seen in Discovery Bay again could be attributed to the small sample size. Further

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. examination into the hourly discharge variation is needed to further understand the significance of these results. The data did suggest tidal amplitude responses to the lunar cycle in the 7:00am measurements of White Pole Spring from each collection day. This is again in agreement with Cable et al. (1997b) who found that although tidal cycle influences were negligible, long-term temporal variation on the order of weeks to months proved substantial. For Discovery Bay, a more definitive explanation can not be achieved due to the lack of statistically significant evidence. It would be important for future studies to be conducted across multiple tidal cycles and at set intervals from high and low tide to obtain the true effect the tides play on discharge. Salinity mapping conducted by Kramer (2009) of the same two springs, White Pole and East Jetty, show similar salinity values all above 20 ppt. These values suggest that mixing occurs between the terrestrial and marine environment before entering the bay. The stable salinities seen directly before and after the spring heads of White Pole Spring indicate that little to no lateral mixing with the marine environment occurs until the ground water reaches the surface. Contrastingly, the East Jetty Spring shows a great deal of lateral mixes especially to the western side of the spring head and partially to the northern side as well. Kramer (2009) found increased algal cover to the west of the spring compared to the right. This could be attributed to the rapid mixing of the nutrient rich ground water with the surrounding marine environment in that direction. The North-South transect line illustrates a northward drift which disagrees with Kramer (2009) surface salinities that suggested overall drift was to the southwest. The source of the rapid mixing could be the strong North-Easterly winds in the area that affect the East Jetty Spring more so than the White Pole. It is also deeper which may provide more time for the mixing to occur. The presence of mixing in the spring with only 1 dominant head and no mixing in the spring with 3 heads is in disagreement with Renchen (2008) who stated that springs with multiple seeps compared to one main head allow groundwater to mix more freely. REFERENCES Andersen MS, Baron L, Gudbjerg J, Gregersen J, Chapellier D, Jakobsen R, Postma D (2007) Discharge of nitratecontaining groundwater into a coastal marine environment. Journal of Hydrology 336(1-2): 98-114. Aronson RB, Precht WF (2000) Herbivory and algal dynamics on the coral reef at Discovery Bay, Jamaica. Journal of Limnology and Oceanography 45: 251-255. Bokuniewicz HR, Buddemeier B, Smith MC (1988) The typological approach to submarine groundwater discharge (SGD). Biogemchemistry 66: 145-158. Bonem RM (1988)Effects of submarine karst development on reef succession. Coral Reef Symposium 3: 419-423. Burnett WC, Aggarwal P, Aureli A, Bokuniewicz H, Cable J, Charette M, Kontar E, Krupa S, Kulkarni K, Loveless A

(2006) Quantifying submarine groundwater discharge coastal zone via multiple methods. Science of the Total Environment 367: 498-543. Cable JE, Burnett WC, Chanton JP, Corbett DR, Cable PH (1997) Field evaluation of seepage meters in the coastal marine environment. Estuarine, Coastal and Shelf Science 45(3): 367-375. Capone DG, Slater JM (1990) Interannual patterns of water table height and groundwater derived nitrate in nearshore sediments. Biogeochemistry 10(3): 277-288. D'Elia FF, Webb KL, Porter JW (1981) Nitrate-rich ground water inputs to Discovery Bay, Jamaica: A significant source of N to local coral reefs. Bulletin of Marine Science 31: 903-10. Gayle PMH, Woodley JD (1998) Discovery Bay, Jamaica. CARICOMP - Caribbean coral reef, seagrass and mangrove sites. UNESCO 17- 33. Giblin AE, Gaines AG (1990) Nitrogen inputs to a marine embayment: The importance of groundwater. Biogeochemistry 10(3): 309-328. Greenaway AM, Gordon-Smith DA (2006) The effects of rainfall on the distribution of inorganic nitrogen and phosphorus in Discovery Bay, Jamaica. Journal of Limnology and Oceanography 51: 2206-2230. Hughes TP (1994) Catastrophes, phase shifts, and large-scale degradation of a Caribbean coral reef. Science 265: 15471551. Johannes RE, Hearn CJ (1985) The effects of submarine groundwater discharge on nutrient and salinity regimes in a coastal lagoon off Perth, Western Australia. Coastal Marine Science 21(6): 789-800. Lapointe BE, Littler MM, Littler DS (1997) Macroalgal overgrowth of fringing coral reefs at Discovery Bay, Jamaica: Bottom-up versus top-down control. In: Lessios HA, MacIntyre IG, McGee M, editors. Proceedings of the 8th International Coral Reef Symposium. Panama: Smithsonian Tropical Research Institute; 927-932. Littler DS, Little MM (2000) Caribbean Reef Plants. Offshore Graphics, Inc, Washington, DC. Lewis J (1987) Measurements of groundwater seepage flux onto a coral reef: spatial and temporal variations. Journal of Limnology and Oceanography 32: 1165-1169. Lewis J (1987) Measurements of groundwater seepage flux onto a coral reef: spatial and temporal variations. Journal of Limnology and Oceanography 32: 1165-1169. Folger, GF, JD Renchen and EJ Burge. 2010. Groundwater

Nutrient input through submerged groundwater discharge

KORALLION nutrient inputs to a back reef tropical lagoon. MarSci. Online Journal for Undergraduate Research in Marine and Aquatic Science. 9: 1-10. Szmant AM (2002) Nutrient enrichment on coral reefs: Is it a major cause of coral reef decline? Estuaries 25(4): 743766. Valiela I, Costa J, Foreman K, Teal JM, Howes B, Aubrey D (1990) Transport of groundwater-borne nutrients from watersheds and their effects on coastal waters. Biodegradation 10(3): 177-197. Woodley JD (1981) Hurricane Allenâ&#x20AC;&#x2122;s impact on Jamaican coral reefs. Science 214: 749-755.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

Carbonate Concentration of Beach Sediments in Discovery Bay, Jamaica as a Proxy for Coastal Beach Erosion Ronald W Cash Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527

Abstract â&#x20AC;&#x201D; Sediments found on beaches in Discovery Bay, Jamaica are of predominately carbonate origin. These carbonate sediments are mainly derived from coral reef debris and the surrounding biota in the reef ecosystem. The beaches will be at risk for erosion and land loss will become an issue as sea level rises, ocean acidification occurs, and coral reef habitats are destroyed. Samples were collected from a local beach along a transect every ten feet for 270 feet in the breakers and landward. These sediment samples were sieved in order to determine mean grain size, standard deviation, sorting, and cumulative weight percentage. The samples were also treated with 10% HCL- to determine carbonate concentration. Sediments in the bay were poorly sorted and very coarsely sorted. They were also of a high carbonate concentration (70.55% on average). These factors may lead to beach erosion and a loss of land, recreational beaches, and storm protection for the local people of Discovery Bay. Keywords â&#x20AC;&#x201D; Carbonate, Erosion, Discovery Bay, Sediments.

INTRODUCTION

DISCOVERY BAY, JAMAICA are of a predominantly carbonate origin. These carbonate sediments are derived from living creatures which inhabit the nearby coral reefs. Contributors to the carbonate sediment include a wide range of skeletal organisms (e.g., corals, foraminifera, molluscs, echinoids) as well as a number of important algal groups that secrete calcium carbonate within their tissue structure (Perry et. al. 2006). These natural processes build beach materials on the local beaches and in surrounding coastal regions (Goreau et al. 1973). As human interaction with the land and water in this area increases, production of carbonate within the reef may be compromised. These interactions could lead to reduced production of the beach sediments in this area. This may result in localized beach erosion and/or beach retreat in this area, leading to adverse effects for the local population. In the last 40 years, numerous cycles of bleaching and coral diseases have been observed in Discovery Bay, Jamaica (Goreau et al. 1998; Goreau and Hayes 2005). Increasing global temperatures have also been noted to adversely affect coral growth and coral reef viability (Graham et al. 2008). Algae species such as Halimeda are also a very important contributor to the sediment input of the surrounding areas of Discovery Bay, Jamaica (Liddell et al. 1988). The algae species may also be an important input of calcium carbonate sediment to the beaches of Discovery Bay as well. These calcareous algae species are predominant fore-reef benthos which can be the major producer of calcium carbonate sediments in the areas devoid of coral. Although these algae species can be important producers of sediment, they may be HE SEDIMENTS WITHIN

vulnerable to similar processes which destroy local reef populations. The sediments which are produced from the Carbonate coral reefs and from the algae species in this area are primarily from dead skeletal materials and pieces which have been broken off via biological processes such as burrowing or consumption, or by natural processes such as disease or bleaching events (Liddell et. al. 1988). Since the 1970s, the Caribbean has seen upwards of a 40% loss in coral reef cover (Gardner et al. 2003; Arronson and Precht 2006). These events have wide ranging effects on the coastal areas adjacent to the reefs, including loss in biodiversity and loss of sediment due to a loss of incoming carbonate sediments to replace those which have been eroded (Spencer and Viles 2002). It can only be assumed that as global warming continues, more stresses on these environments, such as increased storm frequency, ocean acidification and rising sea level, will only continue to decrease the amount of carbonate sediments delivered to the beaches of Discovery Bay. It is very important to know exactly how much the beaches within Discovery Bay, Jamaica are comprised of these carbonate sediments. The beaches in this area are important for the local population as a recreational area and for tourism. The concentration of carbonate within these beach sediments will be vital in understanding how the complex interactions of the coral reef system will affect the sedimentation of local beaches. This information may be used for future plans to preserve the beaches of this area and to understand how they will be affected by coral loss. MATERIALS AND METHODS Study sites and geographic data Sediment samples were collected in May 2010 in Discovery Bay, Jamaica. Sediments were collected every 3.048 meters (10ft.) along a distance of 82.296 meters down the beach (270 ft.) Samples were collected in two different areas of the beach, in the breakers (called seaward) and in the area of the beach closest to the land (called landward). These samples were collected in this manner in order to give a complete average for the beach facies. Data Collection. Sediments were collected at the Discovery Bay Public beach every 3.048 m (every 10 feet) at both the top of the beach and along the breakers. These samples were then dried using a conventional sediment oven set to 71o C for 24 hours. A portion of each sample was then sieved using half-phi size sieves in a range from -1 to 4 in order to determine the mean phi size (Equation 1), standard deviation (Equation 2) and the

Carbonate concentration of beach sediments in Discovery Bay, Jamaica

KORALLION

(1) Graphic Mean Phi Size (Φ16 + Φ50 + Φ84) / 3

landward and seaward sample. (Figure 1). Both of these numbers show that sediments in this area are very coarse as compared to a normal of 0 phi. 160 140 Sediment Mass (g)

sediments inclusive graphical skewness (Equation 3). These parameters were determined using the cumulative phi percentage. Cumulative phi percentage is determined by adding each cumulative percentage of each phi size. This also gave an idea of percentages of the beach sediment that were gravel, sand, and mud fraction. Sieving was done using standard ES-11 sieves. 10 grams from each sediment sample were then placed in a beaker. 200 mL of 10% HCL- was then added in order to dissolve any carbonate in the sample (Equation 4).

60 40

-1 -0.5 0 A. Landward

0.5 1

1.5

2 2.5 3 3.5 4

4.5

Phi Size

160 140 120 Sediment Mass (g)

Each sample was allowed to dissolve in the beaker for six hours to ensure complete dissolution. The initial mass of the acid, the initial mass of the sediment, and the initial mass of the beaker was then summed. This number was then subtracted by the final mass of the HCL- and sediment solution, which yields the total carbonate (Equation 5). The mass of the carbonate was then used to calculate the percentage of carbonate within the beach samples.

(4) CaCO3 + 2HCl- = CaCl2 + CO2 + H2O (5) (Initial Mass of Acid + Initial Mass of Sediment) Mass after Reaction = Mass of Carbonate

100

(2) Inclusive Graphic Standard Deviation (Φ84 - Φ16) / 4 + (Φ95 - Φ5) / 6.6 (3) Inclusive Graphic Skewness [(Φ84 + Φ16 - 2Φ50 ) / 2(Φ84 - Φ16)] + [(Φ95+ Φ5 - 2Φ50) / (2 Φ95 - Φ5)]

120

100 80 60 40 20 0 -1 -0.5 0 0.5 1 1.5 2 2.5 3 3.5 4 4.5 Phi Size

Analyses Analyses of cumulative weight percentages, phi size distribution, and Calcium Carbonate percentage were done in Microsoft Excel. Cumulative weight percentage was graphed in a manner in which individual phi size percentages used in equation 1-equation 5 could be seen. Carbonate percentages were calculated individually and plotted using Microsoft Excel. RESULTS Phi Size Distribution and Cumulative Weight Percentage Sieving of each sample in Discovery Bay, Jamaica revealed a graphical mean grain size of 0.5 phi for sediments collected in the breakers, and a graphical mean grain size of 0.2168 phi in the samples collected in the landward side of the beach. These samples also had an inclusive graphic standard deviation of 1.3689 phi for samples collected in the breakers and of 1.4542 phi for samples collected in the breakers. These numbers suggest that samples collected in both areas are poorly sorted. The inclusive graphic skewness of each sample was calculated as well, yielding a skewness of 0.5233 for samples in the breakers, and 0.8142 in landward samples. This skewness can be seen in the phi size distributions of both 22

B. Seaward Figure 1. Phi size distribution of sediments based on phi size. The distribution graphs of both landward and seaward samples show a very coarsely skewed sediment distribution along both transects.

Cumulative weight percentage is used for numerous sedimentological calculations that are used in the study of sediment processes. The cumulative weight percentage graph shows the cumulative weights of each individual phi size collected up to one hundred percent (Figure 2). Calcium Carbonate Percentages Calcium carbonate percentages were taken from every sample taken both landward and seaward. Carbonate percentages from samples collected landward samples were much less variable than those found in samples collected in the breakers. The percentages of individual samples in the landward are shown in Figure 3 and have an average carbonate concentration of 69.5% and a range of percentages from a low of 61% to a high of 80%. Samples collected from the breakers individual carbonate percentage are shown in Figure 3. Seaward samples were found to be much more variable, having an average carbonate concentration of 71.6% and a range of 55% on the lowest concentration and of 95% on the high end.

Carbonare Percentage

Cumulative Percentage

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

100 80 60 40 20 0 -1 -0.5 0

0.5 1

1.5

2 2.5

3 3.5

4 4.5

100% 95% 90% 85% 80% 75% 70% 65% 60% 55% 50% 0

90 120 150 180 210 240 270

Distance Down Beach (ft.) B. Seaward Figure 3. Carbonate percentage down the beach in both landward and seaward samples.

Phi Size

Cumulative Percentage

A. Landward

100 90 80 70 60 50 40 30 20 10 0

DISCUSSION

-1 -0.5 0

0.5 1

1.5

2 2.5

3 3.5

4 4.5

Phi Size

B. Seaward Figure 2. Cumulative weight percentage shows a large percentage of sediments are coarse in the samples taken in Discovery Bay, Jamaica.

100%

Percent Carbonate

95% 90% 85% 80% 75% 70% 65% 60% 55% 50% 0

90 120 150 180 210 240 270

Distance Down Beach (ft.) A. Landward

Samples collected on both landward and seaward transects were a majority coarse sediment. Landward samples had a mean phi size of 0.2168 phi and seaward samples had a mean phi size of 0.5. Both of these samples have a mean phi size congruent with coarse sand. These large grain sizes will be more resistant to erosion due to increased mass and more resistance to erosional processes (Law et al. 2008). This larger grain size may be slightly more resistant to erosional processes; however, the standard deviation numbers reveal poorly sorted environments. Landward samples had a standard deviation of 1.3869 phi and seaward samples had a 1.4542 phi standard deviation. The poor sortedness of these samples may cause an increase in erosion due to a mixture of small and large phi sizes (Anthony and Hequette 2007). The poor sorting in this area may also lead to an increased erosional rates by increasing the porosity of the sediments, or the space in between sediments. This porosity may allow smaller grain sizes to erode away by giving space and a transport media for sediments to escape. Carbonate percentages shown in Figure 3 are shown to have a very variable carbonate concentration. A majority of coral reef derived carbonate sediments are derived from gastropods, pelecypods, corals, and coraline algae (CarranzaEdwards et al. 1995). Although it is unknown how much of the local beaches sediments are made up of coral fragments, gastropods and pelycepods, and how much is comprised of corraline algae species, a major portion of sediments are derived from coral fragments and from animals which depend on the reef. Since the 1970s, coral reefs in Discovery Bay, Jamaica have seen a 40% loss in coral cover (Arronson and Precht 2006). This loss of coral cover will undoubtedly lead to a loss in carbonate productivity. Other fears for beach erosion are ocean acidification and climate change. As atmospheric CO2 rises due to industrialization and needs for transportation, excess CO2 will be pushed into the oceans, forming a weak carbonic acid which may cause calcium carbonate dissolution. Not only will ocean acidification cause a reduction in coral sediment production, but it will also cause a reduction in corraline algae

Carbonate concentration of beach sediments in Discovery Bay, Jamaica

KORALLION production (Obura et al. 2009). Climate change and higher temperatures may also lead to large scale bleaching events, which may also reduce coral productivity (Baker et al. 2008). This loss in carbonate production will also lead to a reduction in incoming sediment to the local beaches. This loss of sedimentation, rising sea levels,and ocean acidification will all lead to possible land loss, a loss of recreational areas, and a loss of storm protection for people living in the coastal areas of Discovery Bay, Jamaica. ACKNOWLEDGMENT The author would like to thank Discovery Bay Marine Lab for support and services during the duration of this study. The author would also like to thank Dana Putman for assistance in processing samples, and Jessica Keller for assistance in the collection of beach samples.

REFERENCES Anthony EJ, Hequette A. The grain size characteristics of coastal sand from the Somme Estuary of Belgium: sediment sorting processes and mixing in a tide and storm sominated setting. Sedimentary Geology. 202 (3): 369382. Aronson RB, Precht W (2006) Conservation, precaution, and Caribbean reefs. Coral Reefs. 25: 441-450. Baker A.C, Glynn PW, Riegl B (2008) Climate change and coral reef bleaching: An ecological assessment of longterm impacts, recovery trends and future outlook. Estuarine Coastal Shelf Science. 80 (4): 435-471. Boggs S (1995) Principles of sedimentology and stratigraphy. Englewood Cliffs, NJ: Prentice Hall. Print. Carranze-Edwards A, Rosalez-Hoz L, Santiago-Perez S (1995) A reconnaissance study of carbonates in Mexican beach sands. Sedimentary Geology. 101 (3): 261-268. Folk RL, Ward WC (1957) Brazos River Bar: A study in the significance of grain-size parameters. Journal of Sedimentology and Petrology. 27: 3-26. Gardner TA, Cote IM, Gill JA, Grant A, Watkinson AR (2003) Long-term region-wide declines in Caribbean corals. Science. 301: 958-960. Goreau TF, Goreau NI (1973) Coral reef project papers in memory of Dr. Thomas F. Goreau. 17. The Ecology of Jamaican Coral Reefs. II. Geomorphology, Zonation, and Sedimentary Phases. Bulletin of Marine Science. 23: 399464. Goreau TF, Hayes RL (2005) Global coral reef bleaching and sea surface temperature trends from satellite-derived hotspot analysis. World Resource Review. 17: 254-293.

Goreau TJ, Cervino J, Goreau M, Hayes R, Hayes M, Richardson L, Smith G, Demeyer K, Nagelkerken I, Garzon-Ferrera J, Gil D, Garrison G, Willams EH, Bunkley-Williams L, Quirolo C, Patterson K, Porter JW, Porter K (1998) Rapid spread of diseases in Caribbean Coral Reefs. Revista de Biologia Tropical. 46: 157-171. Graham NAJ, McClanahan TR, MacNeil MA, Wilson SK, Polunin NVC, Jennings S, Chabanet P, Clark S, Spalding MD, Letourneur Y, Bigot L, Galzin R, Ă&#x2013;hman MC, Garpe KC, Edwards AJ, Sheppard CRC (2008) Climate warming, marine protected areas and the ocean-scale integrity of coral reef ecosystems. PLoS ONE 3: e3039. Kinsey DW, Hopley D (1991) The significance of coral reefs as global carbon sinks-response to greenhouse. Paleogeography, Paleoclimatology, Paleoecology. 89: 363-377. Law BA, Hill PS, Milligan TG, Curran KJ, Wilberg PL, Wheatcraft, RA (2008) Size sorting of fine grained sediments during erosion: Results from the Western Gulf of Lions. Coastal Shelf Research. 28: 1935-1946. Liddell WD, Sharon LO (1988) Hard substrata community patterns, 1-120 M, North Jamaica. Palaios. 3: 413-423. McManus JW (2009) Coral reefs. Encyclopedia of Ocean Sciences. 660-670. Morse JW, Arvidson RS (2002) The dissolution kinetics of major sedimentary carbonate minerals. Earth-Science Reviews. 58: 51-84. Obura DO (2009) Reef corals bleach to resist stress. Marine Pollution Bulletin. 56: 206-212. Perry CT, Taylor KG, Machent PG (2006) Temporal shifts in reef lagoon sediment composition, Discovery Bay, Jamaica. Estuarine, Coastal and Shelf Science. 67: 133144. Spencer T, Viles H (2002) Bioconstruction, bioerosion and disturbance on tropical coasts: coral reefs and rocky limestone shores. Geomorphology. 48: 23-50. Veron JEN, Hoegh-Guldberg O, Lenton TM, Lough JM, Obura DO, Pearce-Kelley P, Sheppard CRC, Spalding M, Stafford-Smith MG, Rogers AD (2009) The coral reef crisis: The critical importance of <350ppm CO2. Marine Pollution Bulletin. 58: 1428-1436. Vousdoukas MI, Velagrakis AF, Kontogianni A, Markrykosta EN (2009) Implications of the cementation of beach sediments for the recreational use of the beach. Beach Tourism Management. 30(4): 544-552.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Marking and Monitoring the Growth, Health and Location of Acropora Colonies in Discovery Bay, Jamaica. John Crooks Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527

Abstract — Over the last three decades, the reef systems of the Caribbean have been undergoing a shift in community structure. Historically, the region has been dominated by a calcareous benthos, but it is now switching towards a macro algae dominant system. Acropora palmata is one of three pivotal coral ecosystem engineers in the Caribbean. In Discovery Bay, Jamaica, Acropora palmata and cervicornis once flourished both on the fore reef and within the bay. Due to hurricane damage, disease, bleaching events and overfishing, the resident population levels have seen significant decline. A. palmata provides both economic and biological value to the surrounding people and region. With this phase shift in progress it is more important than ever to monitor the population of this important species. In this study, colonies of A. palmata were located, marked, photographed, measured, and had their coordinates taken in an effort to begin an annual monitoring program. A non-linear trend was observed between the volume of the coral stands and the depth at which they were growing. Keywords — Acropora, Coral, Discovery Bay, Jamaica, population monitoring

INTRODUCTION

ORAL, coralline algae, and algal turfs have historically dominated Caribbean reefs. Reefs provide a critical habitat for a diverse and unique array of organisms. Typical coral zonation patterns have been seen in Pleistocene and Holocene reef deposits throughout the Caribbean, and have shown that Acropora spp. play an integral role as framework builders in the past. In the Florida Keys, A. palmata was the dominant structural worker of spur and groove reefs, with spurs of several meters in height and nearly 15 meters in length formed in the 1960s and 70s (ABRT 2005). Acropora palmata typically shows dominance at reef crests and the shallow portions of the fore reef (< 5 m depth) with higher wave energy tolerance, and Acropora cervicornis will be found at intermediate depths (5 – 15 m) along the fore reef where it is more sheltered from direct wave action (Aronson and Precht 1997). It has one of the highest growth rates among Caribbean coral at 12 cm / yr (Tunicliffe 1981). Acropora species reproduce asexually but also have a fairly unique ability to reproduce via fragmentation and re-growth, which gives them a major advantage for distribution and success over other types of coral as well as the ability for further means of proliferation (Tunicliffe 1981). The ability to fragment and re-attach is the species’ dominant method of reproduction. Once a year, the colonies will release their eggs and sperm simultaneously during a mass-spawning event. After 78 hours, the larvae gain motility and within five days are able to begin settling; however, they can remain planktonic for nearly three weeks (Baums et al. 2005). This research was conducted as part of the Coastal Carolina University classes MSCI 477, Ecology of Coral Reefs, and MSCI 499, Directed Undergraduate Research, in Discovery Bay, Jamaica, 12-30 May 2010

Acropora populations throughout the Caribbean have declined in abundance significantly over the last four decades. As of 2008, they have been listed as threatened and put on the United States’ endangered species list. This decline has been due to multiple different stressors on the community; however, a few stand out above the rest. Evidence suggests that these are both natural stresses as well as anthropogenic, such as nutrient loading, excess sediment input and direct damage to the reefs themselves (Wapnick et al. 2007; Wilkinson and Souter 2008). Over the past two decades many new coral diseases have been discovered, such as white pox in A. palmata, blackband, yellow blotch and rapid tissue loss (associated with an unknown epizootic organism); however, very little is known about these pathogens (Williams and Miller 2005; Patterson et al. 2002). Globally, 29 coral diseases have been described, of which 9 have been found to be Caribbean specific. Goldberg and Wilkinson (2004), suggest that nearly 85 % of Carribean coral species are susceptible to disease, whereas only about 25% of species in the Indo-Pacific are susceptible. One such example is whiteband disease (WBD), which is a bacterial infection that is characterized by band-like segments of bare skeleton with adjacent sleeves of dying tissue on the branches of Acropora, as can be seen in Figure 1. It tends to spread from the base of a branch or colony to the top, and has the ability to kill a whole colony (Wapnick et al. 2007). WBD was first spotted in Discovery Bay in 1980, and between 1982 and 1986 nearly 95 % of marked colonies on the fore reef suffered mortality due to its presence (ABRT 2005). It’s debated to be one of the leading causes of the mass mortality of the Caribbean Acropora populations in the 1980s. Mass bleaching events have been observed to precede many of these disease outbreaks. Bleaching is the expulsion of photosynthetic algal endosymbionts. This expulsion often occurs due to temperature change. In 1998, there was a global bleaching event that caused 20 - 99 % mortality in the Pacific and Indian Oceans due to El Nino. In this same occurrence, the Caribbean saw 60 – 80 % bleaching induced mortality (Clark et al. 2009). Temperature changes of 0.5 - 2.0 °C above the seasonal average can be enough to induce bleaching (Clark et al. 2009). In 2005, the Caribbean waters were the warmest they had been in the previous 20 years, resulting in increased thermal stress on the reefs, which led to mass bleaching and increased outbreak of white band and yellow blotch disease resulting in a 26 – 48 % coral cover loss in the Virgin Islands (Mao-Jones et al. 2010). Hurricanes have also been described as a major desiccating force among these species. Hurricane Allen in 1980 hit the north coast of Jamaica and caused a reduction in cover of A. cervicornis by 99 % and A. palmata by 85 % (ABRT 2005). After the storm had passed, mortality numbers

Acropora colony growth, health, and location in Discovery Bay, Jamaica

KORALLION

Figure 1. Acropora palmata colony on the western fore reef of Discovery Bay, Jamaica.

of A. cervicornis and A. palmata fragments reached 98 % due to grazing snails, sea urchins and other predators who were relatively unaffected by the hurricane (Porter 1987). During the last 30 years, Discovery Bay has been undergoing an extreme transitional period ecologically. A phase shift from a benthic community, characterized by Acropora coral, is underway and is headed towards a macroalgae dominant community (Idjadi et al. 2006). This shift is also occurring throughout the greater Caribbean region. There are a multitude of factors that are working in harmony to drive this change. Hurricane Allen’s initial desiccation followed by the spread of WBD in the 1980s cleared room for macroalgae to begin recruiting strongly. Overfishing and reduced herbivory from the pelagic community, in combination with increased nutrient inputs of anthropogenic origins, allowed the macroalgae communities to out compete the coral regrowth. Macro-algal cover has increased in some regions from < 5% to well over 60% (Aronson and Precht 2001). Acropora species have been considered ecologically irreplaceable for many reasons. They are essential reef builders in shallow to intermediate waters, creating a broad and complex habitat for a diverse array of organisms to inhabit. They also serve as a buffer for inland and lagoonal communities from high wave energy (Precht and Aronson 2004). Not only are the reefs important for the biosphere, but they are also economically significant. It has been estimated that the monetary value of Caribbean coral reefs, through tourism, fisheries and other services provided 3.1 - 4.6 billion dollars as of 2002, and nearly 64 % of said reefs were threatened by human activity (Wilkinson and Souter 2008). It is crucial that as much knowledge be gained as possible about these unique organisms so that efforts can be made to find a way to sustain and cultivate their growth. This initial survey and assessment is being conducted with the hopes of providing enough baseline population data to begin an annual monitoring program of the Acropora colonies in Discovery Bay, Jamaica. On a side note, it is thought that both the height and volume of colonies will increase with depth. By

Figure 2. Overview of Discovery Bay with the dive locations marked out in the top left corner (from left to right: L.T.S., Dancing Lady, M1).

monitoring the population dynamics and community structure shift over time, the function of transitional reef communities will be better understood. Study sites and geographic data Through consultation with those familiar with the area and relevant literature (Tunicliffe 1981; ABRT 2005; Aronson and Precht 1997; Williams et al. 2006; Porter 1987), the focus of this monitoring program was narrowed down to the western fore-reef of Discovery Bay, Jamaica. The initial survey dives consisted of a sweep along the fore reef from depths of one to ten meters. The search dives started at one of three moorings, M1, L.T.S. shallow, and Dancing Lady, as marked in Figure 2. Data collection Upon locating a colony, a GPS unit, housed in a positively buoyant case attached to a reel, was released and allowed to surface to obtain signal and location. It was then pulled down to depth and the coordinates were recorded for future reference (as described by the ‘deploy and recover’ technique by personal communication with Mark Thome). Due to physical restraints on dive duration, this occurred over the course of many dives. After marking the colonies GPS coordinates, volumetric measurements were taken. This was done according to standards provided by NOAA (Williams et al. 2006). Using a PVC pipe painted with alternating color intervals spanning 10 cm; length, width and height were recorded in centimeters. Length was measured at the widest point of a colonies diameter and width was measured perpendicularly from that. Height was measured perpendicular to the substrate the colony was attached to. Every colony found was also given a unique identification number and photo documented with said ID # and the PVC ruler (for quick size reference). The colony type will be assigned thereafter. This classification includes: Branched colony (BC) – Typical colony with branching arms; Remnant Colony (RC) – consisting of mostly living tissue with few branches; Attached

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 35 30 Number of Colonies

25 20 15 10 5 0 0.75

Fragment (AF) – a living fragment that has reattached to the reef; Stable Fragment (SF) – Large loose fragments that don’t show movement among rubble. Every colony found went through a general health survey. Each colony was examined to determine the percentage of living tissue covering the coral. Bleached portions of a colony were considered still living and were included in the percent living estimate, except where it was deemed a recent mortality or long dead, as defined by Williams et al. 2006. Portions of colonies that have undergone bleaching were also quantified in percentage cover. In addition to these, colonies were examined for evidence of disease, such as white pox and white band disease. Physical damage done by other organisms, in the form of predation or parasitism, such as parrotfish and snail feeding marks or Cliona lesions, was also recorded and photographed. Analyses Mean and standard deviations of abundance, volume and height of A. palmata were determined by grouping by depth. Linear regression analysis was conducted to test for a relationship between height and depth. A non-linear regression was used to determine volume-depth relationships using LPM, where p ≤ 0.05 was considered significant, and the results graphically displayed using Microsoft Excel 2008.

Acropora palmata abundance On the western fore reef of Discovery Bay, 95 Acropora palmata colonies were located over the course of nine survey dives (Figure 3). No A. cervicornis colonies were located on the western reef by any surveyors. Of these colonies 87% were found between 1.5 m and 3.75 m depth, as can be seen in Figure 4. The depths sampled range from 0.607 m to 4.57 m with the average at 2.52 m.

4.5

5.25

Volumetric analysis The colony height frequency is shown in Figure 5, which shows a slight skew to the right. Only 8.89% of the colonies sampled grew above 60 cm. The average height among all of the colonies sampled was 38.11 cm. The average height per depth interval (0.304 m) is shown in Figure 6. The figure shows a very weak relationship. However, the regression analysis, where α = 0.05 and the p-value = 0.238 shows that there is no statistically significant relationship between the depth and the average height of the coral colonies. 30 25 20 15 10 5 0 20

RESULTS

2.25 3 3.75 Depth Interval (m)

Figure 4. Abundance of A. palmata as a function of depth. The highest frequency occurred between 1.5 and 3.75 meters.

Number of Colonies

Figure 3. GPS markers of assessed Acropora palmata growths along the western fore reef of Discovery Bay, Jamaica.

1.5

60 80 Height (cm)

100

120

Figure 5. Frequency and height distribution of A. palmata on the western fore reef. 91.11% of the samples were less than 60 cm in height.

The frequency of colony size is shown in Figure 7 in cubic meters. It is skewed to the right and 90% of the colonies are less than 1 m3 in size. The smallest measured had a rough volume of 2.5x10-4 m3 and the largest was 2.88 m3. A nonlinear regression was performed, where α = 0.05 and the pvalue = 0.0173.

Acropora colony growth, health, and location in Discovery Bay, Jamaica

KORALLION 80

y = -3.7425x + 44.806 2

R = 0.114

60 50

3.5

40 3

30 20 10 4.9

4.3

3.7

3.0

2.4

1.8

1.2

0.6

0.0

Average Volume

Average Height (cm)

in the 2005 mass bleaching event seen through out the Caribbean, up to 95% coral bleaching was reported in and around Jamaica (Wilkinson and Souter 2008). 2005 was the warmest year on average in the northern hemisphere since the late 1800s. On top of the warmer waters, there were 26 named

2.5 R2 = 0.522

2 1.5 1

Depth (m) Figure 6. When coupled with the regression analysis, A weak but statistically insignificant negative relationship is shown between the average height (shown with standard deviation bars) of A. palmata at the depths they were sampled at.

2 3 Depth (m)

Figure 8. A non-linear regression plotted using a second order polynomial trend line. This shows a curious relationship between the average volumes (m3) by depth, with a minimum at approximately 2 meters and rising to either side.

60 50 Frequency

0 0

40 30 20 10 0 <0.25 0.25- 0.50.5 1.0

1.0- 1.51.5 2.0 Volume

2.02.5

2.53.0

Figure 7. The Volumetric (m2) frequency of Acropora palmata in Discovery Bay, Jamaica. It is heavily skewed to the right, with 53% of the samples having a volume less than 0.125m3.

DISCUSSION The major goal of this study was to provide a baseline data set, and make it available for future studies, to which it was a success. 95 colonies were sampled in all; however, after spending only a little bit of time on the reef, it is apparent that this is just a small sampling of the total A. palmata population in the local area. The majority of colonies found were between 1.5 and 3.75 meter depth. This in part has to do with the search technique used. Due to dive time constraints, as well as the number of dives available, the search process was focused on processing more colonies than it was totally covering a specific area. No A. palmata colonies were found below five meters, reaffirming statements from previous literature about the zonation of this particular reef. Quinn and Kojis (2008) estimated that there were only 1.3 colonies per 100 m2 of A. palmata on the west fore reef. The population took a major hit 28

0.5

storms and 13 hurricanes. These events came together to cause extensive damage to coral populations in the region. The reefs population has shown signs of improvement from Quinn and Kojisâ&#x20AC;&#x2122; (2008) previous low density estimate. m3 The first hypothesis that was tested suggests that there would be a positive correlation between deeper depths and taller coral stands. This would seem intuitive because deeper depths see less wave energy; however, this may not be the case. By examining the data shown in the histogram (Figure 5), we can see an abrupt drop in the number of colonies larger than 60 cm. This abrupt change in drop in numbers might suggest that there is a mechanism restricting the overall vertical growth of the coral colonies, whether it is biological or physical is unknown. The five tallest samples (ranging between 80 and 120 cm) were found between 1.524 m and 3.048 m and show an inverse relationship, with the tallest being in 1.524 meters of water. When plotted and analyzed, the average height by depth interval showed a negative trend, albeit a very weak one. The analysis of variance, using a 95% confidence interval, returned a p-value of 0.238, showing that there is no statistically significant relationship between depth and the average height of Acropora palmata. Given more time for sampling, one might try and measure the average wave energy with depth and then correlate that to the given height of Acropora colonies. The second hypothesis, that there would be increasing colony volume with depth, was found to be mostly correct. The volume of each colony was measured using length width and height as a means of reducing time needed to process each colony. Doing this allowed for more colonies to be sampled, while at the same time still providing useful quantitative information. When the average volumes per depth interval

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 were plotted (Figure 8) a clear trend is seen. A non-linear regression was performed and returned R2=0.522, this coupled with an Analysis of Variance with α =0.05 and pvalue=0.0173 confirm that there is a statistically significant relationship between depth and volume. The average volume decreases from approximately one meter down to two meters before rising with increasing depth. The largest colony found was 3.05 meters deep. One possible reason for this drop in volume around two meters may be due to a more focused range where waves tend to break and roll in. If a wave were to break at a depth of two meters, its energy on the bottom is going to be greater at that two meter depth than it will be at adjacent locations and thus it will have less of an impact on colonies to either side of this energy maximum. This impact zone would be hostile and not an ideal area for unobstructed growth. The volumetric data were taken using a handmade meter stick with ten cm increments painted on. This could have affected the data by causing larger or smaller measurements due to forced rounding of size, causing it to be skewed. During the late morning and early afternoon, the winds tended to pick up in the bay and off the coast. This resulted in higher wave energy on the reef, often causing sub surface surge, which made taking measurements difficult at times. This may have caused a difference in the consistency of measurements, again, causing skewed data. The deploy and recover technique caused some issues while taking coordinates and on more than one occasion caused incorrect replication of waypoints. This was fixed by allowing the GPS to remain on the surface and only reeling it down when taking the waypoint and immediately re-releasing it. It would be of great interest to set up an annual monitoring program where randomly selected colonies are tagged and checked for growth and expansion via NOAA’s monitoring protocol since the distribution on the fore reef appears to be ideal. A proper annual density study across the span of the fore reef would also help monitor the purported shift to an algal dominated benthos

Paleobiology. 23(3): 326-346. Baums IB, Miller MW, Hellber ME (2005) Regionally isolated populations of an imperiled Caribbean coral, Acropora palmata. Molecular Ecology. 14: 1377-1390. Clark R, Jeffrey C, Woody K, Hillis-Star Z, Monaco M (2009) Spatial and temporal patterns of coral bleaching around Buck Island Reef National Monument, St. Croix, U.S. Virgin Islands. Bulletin of Marine Science. 84(2): 167182. Golberg J, Wilkinson C, (2004) Global threats to coral reefs: coral bleaching, global climate change, disease, predator plagues and invasive species. C. Wilkinson (ed.). Status of coral reefs of the world: 2004. Volume 1. Australian Institute of Marine Science, Townsville, Queensland, Australia. 301. Hubbard D K (2008) Depth and species-related patterns of Holocene reef accretion in the Caribbean and western Atlantic: a critical assessment of existing models, Special Publication of the International Association of Sedimentologists. 40: 1-18. Idjadi JA, Lee SC, Bruno JF, Precht WF, Allen-Requa L, Edmunds PJ (2006) Rapid phase-shift reversal on a Jamaican coral reef. Coral Reefs. 25(2): 209-211. Mao-Jones J, Ritchie KB, Jones LE, Ellner SP (2010) How microbial community composition regulates coral disease development. PLoS Biology. 8(3): 1-16. Patterson Kl, Porter JW, Ritchie KB, Polson SW, Mueller E, Peters EC, Santavy DL, Smith GW (2002) The etiology of white pox, a lethal disease of the Caribbean elkhorn coral, Acropora palmata. Proceedings of the National Academy of Sciences of the United States of America. 99(13): 8725-8730.

ACKNOWLEDGMENT The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. Erin Cziraki Scientific Dive Safety Officer, Coastal Carolina University and Erin Burge for guidance and support. Lindsay Harmon, Megan Mudron, Dana Putman, and Nick Krichten, for their tireless assistance collecting data. REFERENCES Acropora Biological Review Team (ABRT) (2005) Atlantic Acropora Status Review Document. Report to National Marine Fisheries Service, Southeast Regional Office. March 3, 2005. 152. Aronson RB, Precht WF (2001) White-band disease and the changing face of Caribbean coral reefs. Hydrobiologia. 460: 25–38.

Porter JW (1987) Species profiles: Life histories and environmental requirements of coastal fishes and invertebrates (south Florida). Reef-building corals. U.S. Fish and Wildlife Service. Biological Report 82: 1-23. Precht WF, Aronson RB (2004) Climate flickers and range shifts of reef corals. Frontiers in Ecology and the Environment. 2(6): 307-314. Quin JN, Kojis BL (2006) Invertabrate recruitment patterns inside and outside Discovery Bay, Jamaica. Proceedings of the 10th international Coral Reef Symposium. 83-90. Tunnicliffe V (1981) Breakage and propagation of the stony coral Acropora cervicornis. Proceedings of the National Academy of Sciences of the United States of America. 78(4): 2427-2431.

Aronson RB, Precht WF (1997) Stasis, biological disturbance, and community structure of a Holocene coral reef. Acropora colony growth, health, and location in Discovery Bay, Jamaica

KORALLION Wapnick CM, Precht WF, Aronson RB (2004) Millennialscale dynamics of staghorn coral in Discovery Bay, Jamaica. Ecology Letters. 7: 354â&#x20AC;&#x201C;361. Wilkinson C, Souter D (2008) Status of Caribbean coral reefs after bleaching and hurricanes in 2005. Global Coral Reef Monitoring Network, and Reef and Rainforest Research Centre, Townsville. Williams DE, Miller MW, Kramer KL (2006) Demographic monitoring protocols for threatened Caribbean Acropora spp. corals. NOAA Technical Memorandum NMFSSEFSC-543. Miami, FL. 91: 1-108. Williams DE, Miller MW (2005) Coral disease outbreak: pattern, prevalence and transmission in Acropora cervicornis. Marine Ecology Progress Series. 301: 119128.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

Variation in covering response of Lytechinus variegatus due to sunlight intensity in Discovery Bay, Jamaica Jen Kisabeth Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract — Lytechinus variegatus is a sea urchin that is mainly found in the Caribbean, and is commonly found in Discovery Bay, Jamaica. This urchin is important to the local area due to the fact that it is a grazer of the macroalgae that inhibits the growth of the coral reefs which were devastated in the 1980s by hurricanes. A wild type and an albino type are the two color variations of this urchin. Due to the lack of the colored pigmentation in the albino urchins, it was hypothesized that albino urchins of this species would cover more of their aboral surface than the wild type. This is because the color pigments of the urchins act as a sunscreen, or light screen, for the urchin, protecting it from the sun’s harmful UV radiation. It was also hypothesized that percent aboral coverage would differ in varying light intensities because of the cost of covering to the urchin. The present study determined the albino urchins covered ~6.70% more than the wild type observationally, and ~3.82% more experimentally. Statistical significances were found observationally between the proportion of aboral surface covered and type of urchin (p = 0.007), time of day (p = 0.000), and habitat (p = 0.002). However, experimentally, statistical significance was only found between proportion of aboral coverage and time of day (p = 0.000). These results indicate that color pigmentation of urchins may play a role in their covering behavior. Keywords — Lytechinus variegatus, Discovery Bay,

Jamaica, covering behavior, sunlight, UV radiation. INTRODUCTION

EA URCHINS are a type of echinoid, an invertebrate with a hard, egg-shaped body and movable spines. They help to control algae populations and because of this, they can have a great influence on the structure of benthic communities (Alves et al. 2001; Verling et al. 2004; Crook 2003; Barnes & Crook 2001; Andrew 1993; Lawrence 2001; Moore et al. 1963). Sea urchins play an important role in maintaining coral reef ecosystems by grazing on the algae that overtakes the solid rock where coral reefs grow. This is especially important in Discovery Bay, Jamaica, where hurricanes destroyed a large amount of the coral reefs and created open space for algae to form (Emel et al. 2006). Many species of sea urchins that live in shallow water cover their aboral surface with materials from their habitats such as pieces of algae, turtle grass, shells, coral rubble, and pebbles (Agatsuma 2001; Sharp and Gray 1962; Lees and Carter 1972; Kehas et al. 2005; Emel et al. 2006; Fierce and Lapin 2004; Millott 1955; Dix 1970; Douglas 1976; This research was conducted as part of the Coastal Carolina University classes MSCI 477, Ecology of Coral Reefs, and MSCI 499, Directed Undergraduate Research, in Discovery Bay, Jamaica, 12-30 May 2010.

Verling et al. 2004; Adams 2001; Crook 2003; Crook and Barnes 2001; Barnes and Crook 2001; Andrew 1993; Verling et al. 2002; Lees and Carter 1972; Dumont et al. 2007; Lawrence 2001; Moore et al. 1963). They accomplish this by using their podia, and spines to gather and hold the material in place. The urchin’s tube feet extend until they reach loose objects to attach to and then they contract to pull the material to the spines where the material is moved (Kehas et al. 2005; Jun et al. 2005; Millott 1955; Agatsuma 2001; Verling et al. 2004; Barnes and Crook 2001; Verling et al. 2002; Lees and Carter 1972; Lawrence 2001; Moore et al. 1963). The tendency of some sea urchins to cover their surface with materials may be affected by a variety of ecological factors. While the type and quantity of covering material used by sea urchins mostly depends on the availability, sea urchins also may pick and choose what type of material they want to use (Amato et al. 2008; Kehas et al. 2005; Verling et al., 2004; Lees and Carter 1972; Lawrence 2001). This is because covering may act as camouflage from predators, protection from wave surge, defense from sediments, or most commonly, for protection from ultraviolet light (Fierce and Lapin 2004; Sharp and Gray 1962; Millott 1955; Dix 1970; Douglas 1976; Kehas et al. 2005; Adams 2001; Crook 2003; Crook and Barnes 2001; Lees and Carter 1972; Andrew 1993; Verling et al. 2002; Dumont et al. 2007; Moore et al. 1963). Light has been shown to cause urchins to cover. Urchins cover more in full sunlight than partial sunlight or darkness (Fierce and Lapin 2004; Douglas 1976; Crook and Barnes 2001; Barnes & Crook, 2001; Verling et al. 2002; Dumont et al. 2007; Moore et al. 1963). This is because the covering helps the urchins to screen damaging solar radiation (Jun et al. 2005; Amato et al. 2008; Verling et al. 2002; Dumont et al. 2007; Moore et al. 1963). In many sea urchins, covering is most common during the daytime. These observations are consistent with the view that the covering response to light may protect sea urchins from damaging solar radiation (Kehas et al. 2005; Verling et al. 2002; Lees and Carter 1972; Dumont et al. 2007; Moore et al. 1963). When grass fragments are covering one half of an urchin and light is shown on the other half, the urchin will transfer the grass to the illuminated half (Jun et al. 2005). Experiments in outdoor containers demonstrated that artificial darkness imposed during natural daylight hours prevented covering (Kehas et al. 2005; Verling et al. 2002). Lytechinus variegatus is a tropical species of sea urchin that lives in the Caribbean. L. variegatus occupies the lagoon and back reef of Discovery Bay. Of this species there are two main types, a wild type and an albino type. The colors that compose the wild type are green and white. These colors vary

Lytechinus variegates in Discovery Bay, Jamaica

KORALLION in shade among individuals so that dark, medium, light, and pale individuals are distinguishable (Sharp and Gray 1962; Millott 1955). This species of urchin lives approximately 3 to 24 feet underwater. L. variegatusâ&#x20AC;&#x2122;s habitat consists of both turtle grass (Thalassia testudinum) and coral rubble (Emel et al. 2006; Narayan and Raffensperger 2005). This is most likely why they usually cover themselves with bits of grass and similar material (Sharp and Gray 1962; Adams 2001). In Jamaica, large numbers of individuals are found almost completely covered (Millott 1955). Animals of all shades cover themselves in their natural surroundings. Some scientists have suggested that the pigment in the skin of echinoids serves as a light screen, and note that species lacking such protection cover themselves with debris (Millott 1955). The present study with L. variegatus uses both field observations and experiments to determine the effects of different light intensities and sea urchin color pigmentation on covering response. The first hypothesis is that the covering of the sea urchins will be less in low light. This is because it is assumed that covering has some cost to the urchin. If there is low light, then the cost of covering would most likely be greater than the damage done by the sun. To test this hypothesis, the covering response of L. variegatus was experimentally determined in different sunlight intensities during several different times of the day: morning, afternoon, evening, and night. The natural covering of the urchins was also observed and compared by estimating the total surface area covered for each urchin both in the field and in the lab. The second hypothesis is that albino sea urchins will cover more than 10% more of their aboral surface than wild-type urchins because the decreased color of albino urchins will increase their vulnerability to solar radiation. MATERIALS AND METHODS Field Observations On May 17 - 18, 2010, the covering behavior of 217 wild type and 199 albino Lytechinus variegatus sea urchins were observed in the lagoon and west back reef of Discovery Bay, Jamaica. The water was one to three meters in depth. The percent cover of the aboral surface of L. variegatus was estimated for each of these urchins as well as the material each was covered with. The environments that each urchin was observed in was also noted (30% turtle grass-70% rubble, 50% turtle grass-50% rubble, and 70% turtle grass-30% rubble). This was done during several times during the day: once in the early morning (7:00 - 8:00am), once in the late morning (11:00am - 12:00pm), once in the afternoon (2:00 - 3:00pm), and once in the evening 7:00 - 8:00pm). Times were chosen to monitor the changes in the covering behavior of L. variegatus over a range of solar radiation intensities. Percent cover and time of day were analyzed for all three environments for both the wild type and albino urchin.

Laboratory methods On the morning of May 22 - 23, 2010, 18 wild type L. variegatus sea urchins and 18 albino L. variegatus sea urchins were collected from the lagoon and west back reef of Discovery Bay. Six urchins of each type (wild type and albino) were collected from each of the previously mentioned habitats. They were collected in a bag and placed in separate holding tanks by habitat with running seawater in the Discovery Bay Marine Wet Lab. From 7:00 - 8:30am on May 23 and 25, 2010, the covering behavior of each urchin was observed in outdoor tanks (24 x 36 x 64 cm) with running seawater in direct sunlight. Each tank had a sandy bottom (1 cm deep) and contained the same covering material: 40 blades of turtle grass (1.5 x 10 cm) and 40 pieces of coral rubble (3-5 cm in length) collected from the lagoon and west back reef. Two urchins were placed in each tank and the percent of covering and material was recorded after 15 minutes. The effect of color (wild type or albino) was analyzed with percent covering, material, and habitat for each time of day. These procedures were performed three more times, once in the late morning (11:00am - 12:30pm), once in the afternoon (2:00 3:30pm), and once in the evening (7:00 - 8:30pm) for a total of four solar radiation levels. Water temperature was kept constant over all trials (27oC - 30 oC). RESULTS The aboral surface covering behavior of L. variegatus urchins, color type (wild type or albino), and habitat were quantitatively examined for both observational and experimental data to illustrate significance between each of the four experimental light regimes. In this study both observational and experimental results showed similar data trends.

Field Observations Field observations indicated that, in each of the three habitats, albino L. variegatus urchins, on average, covered significantly more of their aboral surface than did the wild type L. variegatus urchins (~6.70% more). Both the albino and wild type L. variegatus urchins significantly covered more of their aboral surface in the late morning (~90.85% coverage) followed by the afternoon (~90.01%), early morning (~79.84%), and evening (~34.04%). Observations also indicated that urchins in the 50% turtle grass to 50% coral rubble habitat significantly covered their aboral surface the most of the three habitats (~78.76% coverage), followed by the 30% turtle grass to 70% coral rubble (~73.38%), and 70% turtle grass to 30% coral rubble (~68.14%) (Figure 1). Statistical significances were found among the proportion of aboral surface covered with the type of the urchin (wild type or albino), the time of day, and the habitat the urchins were initially found in (p = 0.007, p = 0.000, and p = 0.002 respectively) (Table 1).

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. c) Observational One-way ANOVA: Proportion Coverage versus Habitat Source Habitat 0.002 Error Total

MS 2

411 413

25.3662 26.1490

F 0.7828

P 0.3914

6.34

0.0617

A two-sample t-test was performed on the observational data to determine the estimated difference between the proportions of the aboral surface covered with the type of the urchin (wild type or albino). This value was found to be 6.70% and is depicted in Table 2. Table 2. Two-sample t test depicting the estimated difference between the proportion of the aboral surface covered with the type of the urchin (wild type or albino L. variegatus). Two-Sample T-Test and CI: Proportion Coverage, Type Type

Mean

StDev

SE Mean

198 0.243 216

W 0.256

0.768 0.017 0.701 0.017

Difference = mu (A) - mu (W) Estimate for difference: 0.0670 95% CI for difference: (0.0188, 0.1152) T-Test of difference = 0 (vs not =): T-Value = 2.73 , p-Value = 0.007, DF = 411 Figure 1. a) Graphical representation illustrating observational average percent aboral surface coverage of the wild type L. variegatus sea urchin in three different habitats (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble) during four sunlight intensities during the day (7:00am, 11:00am, 2:00pm, 7:00pm). b) Graphical representation illustrating average percent aboral surface coverage of the albino L. variegatus sea urchin in three different habitats (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble) during four sunlight intensities during the day (7:00am, 11:00am, 2:00pm, 7:00pm). Table 1. a) ANOVA showing the relationship between the proportions of the aboral surface covered and type of urchin (wild type or albino L. variegatus). b) ANOVA showing the relationship between the proportion of the aboral surface covered and the time of day (7am, 11am, 2pm, 7pm). c) ANOVA showing the relationship between the proportion of the aboral surface covered and initial habitat (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble). a) Observational One-way ANOVA: Proportion Coverage versus Type Source

SS F

MS P Type

1 0.4635

Error

0.4635 7.43 25.6855

412

0.007

0.0623 Total 413 26.1490 b) Observational One-way ANOVA: Proportion Coverage versus Time Source P Time

SS 3

7.65526 Error

F 22.96577

985.99 3.18324

410 Total

413

0.000 0.00776 26.14902

Laboratory Observations Similar to the field observations, experimental observations also indicated that, in each of the three habitats, albino L. variegatus urchins, on average, covered significantly more of their aboral surface than did the wild type L. variegatus urchins (~3.82% more). Both the albino and wild type L. variegatus urchins significantly covered more of their aboral surface in the afternoon (~93.74% coverage) followed by the late morning (~92.78%), early morning (~79.72%), and the evening (~21.67%). Unlike the observational results, experimental observations also indicated that urchins in the 50% turtle grass to 50% coral rubble habitat generally covered their aboral surface the most of the three habitats (~72.81%), followed by the 70% turtle grass to 30% coral rubble (~71.67%), and the 30% turtle grass to 70% coral rubble (~71.25). However, this was not always the case. There were instances when either one, or both, of the 30% turtle grass to 70% coral rubble or the 70% turtle grass to 30% coral rubble habitat showed more aboral surface coverage, on average, than the 50% turtle grass to 50% coral rubble habitat (Figure 2). Statistical significances were not found between proportion of the aboral surface covered and type of urchin (p = 0.451) as well as between proportion of surface covered and habitat (p = 0.967) (Table 3). A two-sample t test was performed on the observational data to determine the estimated difference between the proportions of the aboral surface covered with the type of the urchin. This difference was found to be 3.82% and is depicted in Table 4. Further examination of the experimental results led to an all Pair-wise Multiple Comparison Procedure, also known as the Holm-Sidak method, to analyze the differences of means when comparing the significance between the

Lytechinus variegates in Discovery Bay, Jamaica

KORALLION different time trials for the experiment. Significance was also determined in this trial for each of the solar radiation levels and is depicted in Table 5.

c) Experimental One-way ANOVA: Proportion Coverage versus Habitat Source Habitat Error Total

DF 2 141 143

SS 0.0063 13.1137 13.1200

MS 0.0031 0.0930

F 0.03

P 0.967

Table 4. Two-sample t test depicting the estimated difference between the proportion of the aboral surface covered with the type of the urchin (wild type or albino L. variegatus). Two-Sample T-Test and CI: Proportion Coverage, Type Type A W

N 72 72

Mean 0.738 0.700

StDev 0.307 0.300

SE Mean 0.036 0.035

Difference = mu (A) - mu (W) Estimate for difference: 0.0382 95% CI for difference: (-0.0618, 0.1381) T-Test of difference = 0 (vs not =): T-Value = 0.76, p-Value = 0.451, DF = 141 Table 5. Pair-wise multiple comparison procedure examining the difference in means between the different time trials of the urchin covering experiment. The overall significance level in this test is 0.05. Comparisons for factor: Time Comparison 11am vs. 7pm 2pm vs. 7pm 7am vs. 7pm 11am vs. 7am 2pm vs. 7am 11am vs. 2pm

Figure 2. a) Graphical representation illustrating experimental average percent aboral surface coverage of the wild type L. variegatus sea urchin in three different habitats (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble) during four sunlight intensities during the day (7:00am, 11:00am, 2:00pm, 7:00pm). b) Graphical representation illustrating average percent aboral surface coverage of the albino L. variegatus sea urchin in three different habitats (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble) during four sunlight intensities during the day (7:00am, 11:00am, 2:00pm, 7:00pm). Table 3. a) ANOVA showing the relationship between the proportions of the aboral surface covered and type of urchin (wild type or albino L. variegatus). b) ANOVA showing the relationship between the proportion of the aboral surface covered and the time of day (7:00am, 11:00am, 2:00pm, 7:00pm). c) ANOVA showing the relationship between the proportion of the aboral surface covered and initial habitat (30% turtle grass to 70% coral rubble, 50% turtle grass to 50% coral rubble, 70% turtle grass to 30% coral rubble). a) Experimental One-way ANOVA: Proportion Coverage versus Type ======================================================= Source Type Error Total

DF 1 142 143

SS 0.0525 13.0675 13.1200

MS 0.0525 0.0920

F 0.57

P 0.451

b) Experimental One-way ANOVA: Proportion Coverage versus Time Source Time Error Total

DF 3 140 143

SS MS 12.54894 4.18298 0.57104 0.00408 13.11998

F 1025.52

P 0.000

Diff of Means t 0.567 49.316 0.563 48.232 0.459 39.318 0.108 9.320 0.104 8.823 0.00428 0.369

Critical Level 0.009 0.010 0.013 0.017 0.025 0.050

Significant? Yes Yes Yes Yes Yes No

DISCUSSION In both the field observational study and the laboratory experiment, it was found that the albino Lytechinus variegatus urchins consistently covered more of their aboral surface with various materials than did the wild type L. variegatus urchins (~6.70% and ~3.82% respectively), signifying that covering behavior of this species of sea urchin may be related to the urchinâ&#x20AC;&#x2122;s color pigmentation. Previous research shows that sea urchins with less pigmentation, or less color, cover more in response to UV radiation (Kehas et al. 2005; Amato et al. 2008; Emel et al. 2006; Sharp and Gray 1962; Millott 1955). Because the albino L. variegatus urchins are missing the colored pigments that the wild type urchins possess, their increased covering behavior may be a sign of greater susceptibility to UV radiation (Emel et al. 2006; Lees and Carter 1972; Sharp and Gray 1962; Millott 1955). The results of this study also showed that the degree of aboral surface covering changed over the different light regimes during the day. This suggests that L. variegatus urchins are able to sense and react to the changing levels of solar radiation by changing their aboral percent cover (Jun et al. 2005). In the present study it was determined that both the albino and the wild type L. variegatus urchins covered more of their aboral surface during periods of more intense sunlight (11:00am and 2:00pm). The urchins decreased the amount of covering on their aboral surface as the amount of light decreased (7:00am and 7:00pm). Because of these results it was determined that sunlight intensity is an important factor in affecting the covering response of L. variegatus sea urchins. Previous studies, like the present study, with sea urchins in

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. different light regimes demonstrated that the urchins in direct sunlight covered themselves to avoid exposure to the damaging UV radiation caused by the sun (Verling et al. 2002; Kehas et al. 2005; Amato et al. 2008; Emel et al. 2006; Lees and Carter 1972; Jun et al. 2005; Sharp and Gray 1962; Millott 1955; Dumont et al. 2007). All the urchins covered very heavily and rapidly in response to sunlight and dropped their covering as the light decreased (Lees and Carter 1972; Kehas et al. 2005; Verling et al. 2002; Jun et al. 2005; Sharp and Gray 1962; Millott 1955). The data of the present study as well as the results of these previous studies strongly suggests that a definite correlation exists between the covering response of L. variegatus urchins and the level of sunlight. Holding covering materials to the aboral surface requires energy, also known as a cost, and may reduce sea urchin respiration, since respiration takes place in the podia, by reducing the number of aboral podia available for gas exchange (Emel et al. 2006; Fierce and Lapin 2004; Kehas et al. 2005; Jun et al. 2005; Dumont et al. 2007). It is believed that because of this, many urchins often drop their covering material at night and cover less in lower light intensities. If they choose to keep their covering, the benefit of the increased cover must outweigh the costs (Emel et al. 2006; Verling et al. 2002; Kehas et al. 2005; Jun et al. 2005). This makes sense because if solar radiation is damaging, there should be a reduced need for protective covering at lower light intensities and at night (Kehas et al. 2005; Jun et al. 2005). In the present study it was observationally determined that initial habitat played a significant role in the covering of L. variegatus urchins. However, the study experimentally determined that initial habitat did not have any statistical significance on the covering. This made determining the initial habitat’s significance difficult. Previous studies indicate that covering material corresponds to the urchin’s initial habitat, meaning whatever is available. This can in turn play a small role on total aboral coverage in that depending on the cost of the available covering material, the urchin may not cover their aboral surface as much as they would if different materials were provided that would cause less cost to the urchin (Emel et al. 2006; Amato et al. 2008; Kehas et al. 2005; Jun et al. 2005; Douglas 1976; Millott 1955). Therefore, it was determined that initial habitat was significant in total percent aboral coverage of L. variegatus when dealing with what covering materials are available to the urchin to use in terms of cost, but not significant in terms of if the urchin’s habitat is changed, their percent aboral coverage may change as well for the same time period of the day. In the present study there were several sources of error. One of which being it was occasionally difficult to estimate the total aboral percent coverage of the urchins that were observed. This was because sometimes the urchins were covered with other urchins, or they were covered, but in spots where it was challenging to decide on a total percentage in the field. A good way to fix this problem in future studies would be to take pictures of each urchin that is observed. This way all the urchins can be looked at simultaneously, making the estimation of percent aboral coverage easier.

Another source of error in this study was the weather. During the course of the observational and experimental portions of the present study the weather was variable. Several rain storms and cloudy days occurred, which could have caused the results to differ or be skewed. Possible reasons for skewed results would be changes in levels of sunlight due to the presence of clouds, changes in water temperature, and changes in water salinity due to the increase in fresh water caused by the rain, several of which could have unknown effects on the results of sea urchin covering. Future studies that could be performed to get a better understanding of aboral covering of L. variegatus sea urchins could include covering in different salinities, in different water temperatures, in different surges or currents, in different water depths, in different visibilities, and while under predation or not. These results when compared with the results of this study as well as other studies would provide a much better understanding of what causes L variegatus to cover and why they cover when they do. ACKNOWLEDGMENT The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. Thank you to Dr. Erin Burge, assistant professor of marine science, Coastal Carolina University; Erin Cziraki, dive instructor, Coastal Carolina University; Fruity, scientific dive safety officer, Discovery Bay Marine Laboratory, University of the West Indies; and Dewayne and Omar, boat drivers, Discovery Bay Marine Laboratory, University of the West Indies. REFERENCES Adams NL (2001) UV radiation evokes negative phototaxis and covering behavior in the sea urchin Strongylocentrotus droebachiensis. Marine Ecology Progress Series 213: 87-95. Agatsuma Y (2001) Effect of the covering behavior of the juvenile sea urchin Strongylocentrotus intermedius on predation by the spider crab Pugettia quadridens. Fisheries Science 67: 1181-1183. Alves FM, Chícharo LM, Serrão E, Adreu AD (2001) Algal cover and sea urchin spatial distribution at Maderia Island (NE Atlantic). Scientia Marina 65(4): 383-392. Amato KR, Emel SL, Lindgren CA, Sullan KM, Wright PR, Gilbert JJ (2008) Bulletin of Marine Science 82(2): 255261. Andrew NL (1993) Spatial heterogeneity, sea urchin grazing, and habitat structure on reefs in temperate Australia. Ecology 74(2): 292-302. Barnes DKA, Crook AC (2001) Quantifying behavioural determinants of the coastal European sea-urchin

Lytechinus variegates in Discovery Bay, Jamaica

KORALLION Paracentrotus lividus. Marine Biology 138: 1205-1212. Crook AC, Barnes DKA (2001) Seasonal variation in the covering behaviour of the echinoid Paracentrotus lividus (Lamarck). Marine Ecology 22(3): 231-239. Crook AC (2003) Individual variation in the covering behaviour of the shallow water sea urchin Paracentrotus lividus. Marine Ecology 24(4): 275-287. Dix TG (1970) Covering response of the echinoid Evechinus chloroticus (Val.). Pacific Science 24: 187-193. Douglas CA (1976) Availability of drift materials and the covering response of the sea urchin Strongylocentrotus purpuratus (Stimpson). Pacific Science 30(1): 83-89. Dumont CP, Drolet D, DeschĂŞnes I, Himmelman J (2007) Multiple factors explain the covering behavior in the green sea urchin, Strongylocentrotus droebachiensis. Animal Behaviour 73: 979-986. Emel SL, Lindgren CA, Sullan KM, Amato KR, Wright PR (2006) Wear sunscreen: Differences in covering behavior and covering material preference in Lytechinus variegatus and Tripneustes ventricosus. In: Peart FEDR, Barrow SELL, Raines SENH, Emel SL, Lindgren CA (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire. Fierce SEB, Lapin HE (2004) Selectivity of covering material in two sea urchins, Tripneustes ventricosus and Lytechinus variegatus. In: Campbell SEEE, Fierce SEB, Tran JK, Wilson EV (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, 166-168. James DW (2000) Diet, movement, and covering behavior of the sea urchin Toxopneustes roseus in rhodolith beds in the Gulf of California, MĂŠxico. Marine Biology 137: 913923. Jun JE, Matsuura TR, Barger MA (2005) Diurnal changes in Tripneustes ventricosus covering response in Thalassia testudinum sea grass beds. In: Sharp SEEA, Barger MA, Jun" PEJE (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, 115-159. Kehas AJ, Theoharides KA, Gilbert JJ (2005) Effect of sunlight intensity and albinism on the covering response of the Caribbean sea urchin Tripneustes ventricosus. Marine Biology 146: 1111-1117. Lawrence JM (2007) Edible Sea Urchins: Biology and Ecology. Habitats: 376-387. Lees DC, Carter GA (1972) The covering response to surge, sunlight, and ultraviolet light in Lytechinus anamesus 36

(Echinoidea). Ecology 53(6): 1127-1133. Millot N (1955) The covering reaction of sea-urchins. I. A preliminary account of covering in the tropical echinoid Lytechinus variegatus (Lamarck), and its relation to light. Department of Zoology and University College of the West Indies, Jamaica, B.W.I. 33: 508-523. Moor, HB, Jutar, T, Baue, JC, Jones JA (1963) The biology of Lytechinus variegatus. Bulletin of Marine Science of the Gulf and Caribbean 13(1), 23-53. Narayan L, Raffensperger JC (2005) Differential patterns of dispersion and abundance in sea urchins Tripneustes ventricosus and Lytechinus variegatus. In: Sharp SEEA, Barger MA, Jun" PEJE (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire, 139-142. Sharp DT, Gray IE (1962) Studies on factors affecting the local distribution of two sea urchins, Arbacia punctulata and Lytechinus variegatus. Ecology 43(2): 309-313. Verling E, Crook AC, Barnes DKA (2002) Covering behavior in Paracentrotus lividus: is light important? Marine Biology 140: 391-396. Verling E, Crook AC, Barnes DKA (2004) The dynamics of covering behaviour in dominant echinoid populations from American and European west coasts. Marine Ecology 25(3): 191-206.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Queen conch, Strombus gigas, densities found in Discovery Bay, Jamaica Alyssa Scott Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract — Queen conch, Strombus gigas, have been researched for many years due to concerns of overharvesting. Populations of S. gigas have been declining in many area of the Caribbean due to the high demand for its meat all over the world. In this study both living and non-living S. gigas were collected and measured to determine the overall density in the Discovery Bay area. The cause of death was also noted. It was hypothesized that there would be 15% more juvenile conch than adult conch. The second hypothesis was that, of the shells collected, the most that were inhabited with fish would be on areas of sandy bottoms. There were more dead conch collected than living, but of the living organisms there were 17 times more juveniles than adults. The majority of the conchs found were in their late juvenile stage (approximately two to three years old) with the majority of the adults collected being in their first stage of adulthood. Keywords — Strombus gigas, densities, Discovery Bay,

Jamaica, population INTRODUCTION

(Strombus gigas) is one of the most important resources in the Caribbean. For many years it has been a source of food for the locals that live there since the Arawak Indians lived in the Caribbean (Stoner et al. 1988). Queen conchs’ meat has been valued since preColumbian times and has been commercially harvested since the mid-18th century (Theile 2001). Local harvesting and distribution was conducted until the method of freezing meat was more common and then meat could be dispersed farther. Since the 1970s there has been a steady increase in the harvesting of S. gigas and it has been exported all over the world. What was once a food source and protein diet for only the local Caribbean people is now being over-harvested in order to keep up with all the demands of foreign countries. Millions of S. gigas are harvested in the Caribbean each year for export and local use (Stoner et al. 1988). This estimate does not include the amount of meat harvested illegally and by local fisherman (Theile 2001). By the mid 1980s and 90s there were concerns raised about the future of the queen conch population by the S. gigas range states (Theile 2001); thus different agencies started forming as a result. In 1992, the Convention of International Trade in Endangered Species of Fauna and Flora (CITES) was established, which categorizes animals in the different species to see how they are affected by national trade. This organization has overseen more than 30,000 species of wild plants and animals. CITES placed the queen conch species, S. gigas, in Appendix II. This category is for species that are not UEEN CONCH

currently under threat of extinction, but could be if international trade was not regulated (Theile 2001). When countries join CITES they have to adopt legislation that allows their country to follow the rules of CITES and their updates. Jamaica became a part of CITES in July of 1997 and started to implement the different rules and legislation for international trade. Jamaica also joined, with many other region states, different organizations and raised their standards so they could trade with the European Union (Theile 2001). Once this occurred there were a few harvesting regulations put out by the Natural Resources Management Unit (NRMU) of the Organization of the Eastern Caribbean States (OECS). These regulations, given in the 1990’s, state that there must be a minimum size restriction, only queen conch with a flared lip could be harvested, only specific types of gear could be used, and detailed location and times for queen conch season closings were set (Theile 2001). By 2003, according to the Department of Planning and Natural Resources Division of Fish and Wildlife, harvesting for S. gigas is allowed if they are a minimum of 9 inches in length (from the spire to its distal end) and have at least 3/8 inch lip thickness (Toller 2003). Commercial and recreational fishermen are limited to 150 conchs and 6 conchs per day, respectively. There is also a closed season from July 1st September 30th (Toller 2003). S. gigas prefer different habitats depending their stage in life. S. gigas juveniles prefer nursery habitats from the sandy shallow areas to sea grass beds that have moderate density to even coral-rubble reef flats (Harborne et al. 2006). Juveniles live emerged in the sediments until these organisms are over one year (about 50 - 70 mm in shell length); during the warmer months they emerge and then disperse into the shallow sea grass beds (Stoner et al. 1988). Adult S. gigas live in water 10-30 m deep; these organisms have also been found at depths of 70 m (Theile 2001, Harborne et al. 2006). Adult S. gigas feeds both during the day and night while juveniles feed only at night. These juveniles can become sexually mature around three or four years old, and an adult queen conch can live to be about 20 years old (Theile 2001). S. gigas were born as pelagic larvae that float along in the currents, about four or five weeks after the hatching these queen conch metamorphose and are completely metamorphosed by the fifth week (Bocttcher and Targett 1996). After the fifth week, they become benthic and grow small shells that will grow with them for the rest of their lives. During the larvae stage, redistribution of the organisms allows for replenishment of S. gigas in different areas due to the current movement (Theile 2001; Bocttcher and Targett 1996). When S. gigas become juveniles, they form aggregations that move together to feed. This large mass of juvenile conch also helps to deter predators (Stoner and Lally 1994; Theile

Strombus gigas densities in Discovery Bay, Jamaica

KORALLION 2001). There are usually two different aggregations that occur in S. gigas: the migration of conch to deeper waters with increasing size and age, in addition to the mating migration where adults move to shallower waters to mate and lay egg masses (Stoner et al. 1988; Davis 2005). During spawning season from March â&#x20AC;&#x201C; October, large aggregations of adult conch are formed for the spawning season (Theile 2001). But the mass migration of juvenile S. gigas that are the same age is a rare event that has only been recorded in a couple of species (Stoner et al. 1988). For some S. gigas they reach sexual maturity around 3 Â˝ 4 years old; this occurs with the thickening of the shell lip (Stoner et al. 1988; Collins and Harrison 2007). In order to be sexually mature the lip thickness has to be five millimeters and some start to form their lip early before they completely grow the length of their shell (Theile 2001). When S. gigas reach sexual maturity they no longer grow their shells as a whole; the length ceases to grow, but the thickening of the flared lip starts to form and continues to grow (Appeldoorn 1988; McCarthy 2007). These conchs are not hermaphroditic but instead they are specifically female and male. The female can mate with more than one male and she will lay many egg masses depending on the weather conditions. At high temperatures and during long photoperiods the maximum egg masses are found, but stormy weather decreases that amount. These egg masses can hold about 300,000 - 1.5 million eggs per mass (Theile 2001). The areas that are best for laying egg masses are the sandy areas because the sand sticks to the eggs and provides good camouflage (Harborne et al. 2006). Once S. gigas die and their shell remains their shells become useful to other creatures that live around the sea grass beds and the coral reefs. Small fish, both juvenile and adult, will live in these shells and will use them for shelter from predators (Wilson et al. 2005). The more shells that are located in one area together, called middens, the more fish live there. This can create an area for more fish to live than would otherwise be not provided if the shells were not there (Wilson et al. 2005). For this study there will be observations made for how many dead versus living S. gigas are found in and around Discovery Bay, Jamaica. This will be accomplished by diving in the sea grass beds, coral reef areas, sandy bottom areas, and hard rock areas. All S. gigas that are seen will be recorded and taken back to the lab, with the exception of shells that provide shelter to fish. Also, of the S. gigas found the age will be determined by the length of its shell and the thickness of its lip (if it has a lip). The ages of live conch will be compared to the number of shells found. The types of fish that are living within those shells will be recorded. For this study there were two hypotheses: (1) that there would be about 15% more living juvenile queen conch found than adults and (2) that out of the shells found there were more fish living in the sandy environment. MATERIALS AND METHODS Study sites Queen conch, S. gigas, was obtained in Discovery Bay, Jamaica by snorkeling and SCUBA diving in locations of coral reefs, sandy bottoms, sea grass beds, and rocky bottom 38

areas. The locations where the SCUBA diving collections occurred were Dancing Lady, Dairy Bull, LTS, M1, East Back Reef, Brink Reef, Dorm Shore, Red Buoy Reef, Lagoon, and Crosby Reef. Data collection Both live organisms and shells of the dead conchs were collected and their locations were recorded. Before collecting S. gigas shells, the shells were observed for a few minutes to see if any fish lived within them. If fish were present, the type of fish was recorded and the shell was measured and then left alone. While in the field, the cause of death was also recorded. If a small hole was found in the apex of the shell, the organism was harvested. If no hole was present it was assumed that the organism died naturally (Collins and Harrison 2007). In the lab the length of the shell, from the tip of the siphonal canal to apex of the spire, was measured and recorded (Collins and Harrison 2007; Toller 2003). The lip was measured for thickness using a caliper to the nearest millimeter. The area that was measured on the lip was about 40 mm away from the end of the lip so that the measurement would show the true growth of the lip. This is because the lip can break or become eroded over time (Appeldoorn 1988). Once the length and lip thickness were recorded, the approximate age can be determined using a predetermined scientific model (Appeldoorn 1988; Collins and Harrison 2007). When all measurements were completed, all live organisms and shells were returned to the habitat which they were found in. RESULTS Strombus gigas collections There were 140 total S. gigas collected. These organisms ranged from small juveniles to old adults. Of the 140 analyzed, 104 were empty shells and 36 were living organisms. The number of harvested adults versus harvested juvenile S. gigas was compared. This graph showed that there was more harvested juvenile conch than harvested adult conch (Figure 1). Once the harvested data was analyzed, there was a comparison of the juveniles and adults that had a natural death. It was observed that there more juveniles died naturally than adults (Figure 2).

Figure 1. Total amount of collected S. gigas that were harvested placed in columns of harvested adults and harvested juvenile.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Figure 2. The amount of S. gigas that had a natural death of the 140 sampled. Natural death consists of anything other than being harvested.

Figure 5. Comparing the amount of living adults versus living juvenile S. gigas that were collected. There were 17 times more living juveniles than living adultscollected during this study.

There were 33 dead adults; this death could have been caused by harvesting or a natural death. The observations showed that there were about 16.5 more dead adults than living adults (Figure 6).

Figure 3. Comparing the collected conch by observing whether most of these organisms were harvested or died of natural causes.

After the adult and juveniles were compared they were then compared within themselves to see whether out of the sampled number if the leading cause of death in S. gigas was mainly due to harvesting or natural causes. First the adults were compared , followed by the juveniles (Figure 3 and Figure 4). From the previous figure (Figure 3) it was observed that there were almost four times more adults that were harvested than adults that died naturally. The harvested juvenile conch versus the natural death of conch was not as large a variation as the adult conchs observing ten more conch dying of natural death than those harvested (Figure 4).

Figure 6. The total amount of adult conchs that were collected pointed to a fishery that had more dead adults than living adults.

Living S. gigas collected Once all of the empty shells were analyzed the living organisms were observed and recorded. Out of 140 S. gigas collected, 36 were living organisms. When these living organisms were separated by age, 34 were juveniles and two were adults (Figure 5).

Comparing shell length and lip thickness of S. gigas It was noted that there were more S. gigas, both living and dead, that had a shell length between about 210 - 250 mm and lip thickness less than 12 mm (Figure 8).

Figure 4. S. gigas juveniles that were collected were compared by harvested death versus natural death.

Figure 7. Of the 104 juvenile S. gigas collected there were about 2 times more dead juveniles than living juveniles.

Of the 56 juvenile S. gigas collected, there were more total dead juveniles than living juveniles but the amount by which they vary is not as high as living versus dead adults. There were 34 living juveniles and a total of 70 dead juveniles, which showed that there were two times as many dead juveniles as there were living (Figure 7).

Strombus gigas densities in Discovery Bay, Jamaica

KORALLION

Figure 8. Using all 140 S. gigas shell lengths and lip thicknesses the trend is that there were the most conch that had a shell length between 210 - 250 mm but very few conch with lip thicknesses above 20 mm.

Figure 10. Among the total adult S. gigas there were three areas of inclines in lip thickness, the highest one was around 10 mm, the second between 20 - 25 mm and the third around 35 mm.

Figure 11. All of the living adult S. gigas that were collected had a lip thickness of around 22 mm thick. Figure 9. The cumulative frequency percentage showed there were exponentially more organisms with longer shell lengths than with shorter shell lengths.

When looking only at the percentage of S. gigas shell length there were very few organisms that had a shell length less than 100 mm. From there the cumulative frequency increased linearly until the longest shell length of 292 mm (Figure 9). After the shell length was compared with both living and non living S. gigas the cumulative frequency percentage was used to observe the trend in living conch shell lengths. This trend showed that there was more living conch that was in the 180-243 mm length range than any other shell length. The adult population of S. gigas was separated from the juvenile population and their lip thicknesses were compared. This data showed that there were many adult conchs whose lip thickness was around 10 mm. The second group of organisms had lip thicknesses between 15 - 25 mm thick. The largest lip thickness was 32.2 mm. (Figure 10). The live adults in the collected S. gigas showed that there were the most conchs around the 22 mm lip thicknesses and from there it steadily declines to zero (Figure 11). Fish living in S. gigas There were 6 fish found living in S. gigas shells out of the 140 that were collected. The fish that were found were the Cocoa Damselfish (Stegastes variabilis), Sunshinefish juvenile (Chromis insolata), juvenile Damselfish, and the Flamefish (Apogon maculatus). The shells that had fish in them were positioned in a way so that the opening of the shell was faced up toward the water column rather than faced down in the sediment.

Statistical Analysis An ANOVA was used to see if there were any significant differences between the lip thicknesses of the combined living and dead S. gigas. This analysis showed that the lip thickness is not different between sites (p = 0.214). DISCUSSION Strombus gigas collected Main collection for S. gigas was on the forereef with few dives along the lagoon. The main forereef sites were M1, Dancing Lady, and LTS. Fewer dives were at different locations around the reef such as Dairy Bull, Columbus Park, Crosby Reef, and Red Buoy Reef. There were also dives in Dorm Shore and the lagoon. The collection period lasted a little over two weeks. From these dives S. gigas were found on various surfaces from sandy bottoms to sea grass bottoms and on harder bottoms of coral (Collins and Harrison 2007). The organisms were placed into three separate groups, living, harvested, or natural death. The way that harvested versus natural death was determined was if there was a small hole that was around the spiral of the shell (Figure 12) (Collins and Harrison 2007). If there was no hole then it is hard to tell whether the organism died from predation or if it died of any other causes, and there was no way to determine how long the conch had been dead. The S. gigas shells alone that were found were not a good way to determine the healthiness of the population because there is no way to determine if the shell was moved to a different location after it died. But from S. gigas shells the comparison between harvested and natural death could be determined for both juveniles and adults. There seem to be more juveniles in the population because more juveniles were harvested and naturally dead

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 (Figures 1 and 2). This could be due to the overfishing population and the regulations on conch harvesting. This supports the fact that over-harvesting is an issue in the Caribbean (Toller 2003; Collins and Harrison 2007; and Davis 2005).

middle range of adults and Group 3 represents the old stage of adults with the largest lip thickness (Appeldoorn 1988). Figure 10 shows representatives of each group but the number of collected living adult conch showed that younger adults were more abundant. Then the middle aged adults were second highest and finally the old adults, of the living adults collected there was only one that fit into the old adult category. Previous studies have shown this similar trend where there are abundantly more young adult S. gigas than any of the older adults. There were also the smallest amounts of old conchs and the middle aged conchs remained in the middle (Appeldoorn 1988). Most living adult lip thicknesses, of the adults that were collected, were in the lower 20 mm (Figure 11).

Figure 12. The small hole , indicated by the red arrow, on the spiral part of the shell shows that harvesting had taken place.

Overall when S. gigas were compared with each other they showed a higher amount of natural deaths than harvested deaths (Figure 4). This could be because S. gigas as juveniles have more natural predators than adults do (Toller 2003). Juveniles have more natural predators because their shells are not as hard as adults and they are preyed upon by different organisms such as porcupine fish, spiny lobsters, crabs, sharks, rays, and other snails (Toller 2003). 36 out of the 140 organisms collected were alive and of those living 34 were juveniles (Figure 5). When observing the data from Figure 5 and comparing the live versus dead juveniles and adults there are notably more juveniles collected than adults (Figure 6 and 7). Overall the organisms that were collected were younger organisms that either had no lip or had a very small lip (Figure 8). These results are similar to Hesseâ&#x20AC;&#x2122;s results of S. gigas found in the Turks and Caicos Islands where there were mainly juveniles more than 10 cm and many did not have lips. Rarely any older adults with thick rounded lips were found (Hesse 1979). In this study there were also very few organisms found with a shell length of 25 - 70 mm which is also shown in Figure 8 (Hesse 1979). Determining Approximate Age of living S. gigas In previous studies the shell length was used to determine the approximate age of S. gigas. Living S. gigas juveniles and adults collected were between one and three years of age. It was determined that there were three classes of shell lengths composed of 88, 126, and 180 mm (Berg 1976). These three length classifications represented approximately 1, 2, and 3 years old respectively (Berg 1976). Of the living S. gigas collected there were was only one organism that fell in the first year of life while the majority of them were in their third year or higher (Figure 9). There is also another way to determine the age of adult S. gigas. This method uses lip thicknesses to determine if the adults are in different groups. Using Appeldoornâ&#x20AC;&#x2122;s study (1988) on age determination and growth there are three groups that represent the approximate age of adult S. gigas. Group 1 represents the younger stage of adults, Group 2 represents the

Figure 11. All of the living adult S. gigas that were collected had a lip thickness of around 22 mm thick.

Fish living in discarded S. gigas shells Out of all 140 S. gigas collected only 6 shells contained fish. This part of the study did not play as large of a role as initially thought. This is mostly due to the fact that these 6 shells were the only shells that were found that were positioned so the opening of the shell was facing up toward the water column. The rest of the shells found were either buried in the sediment or found with their opening facing down in the sediment. Most small, juvenile fish were found living in the shells, supporting previous studies on fish relations with S. gigas (Wilson et al. 2005). The shells provide a habitat that protects small juvenile fish in areas where there is not much structure, for example on sandy bottom areas where there is not much sea grass (Wilson et al. 2005). Juvenile fish will utilize these shells and even groups of shells called middens as a microhabitat and will use it more than surrounding microhabitats. When S. gigas shells are discarded they can be inhabited with fish within 6 days. (Wilson et al. 2005). Conclusion There were 17 times more juveniles as adult S. gigas, suggesting there is a disturbance to cause this difference. This disturbance is overfishing of S. gigas. Many previous studies have researched and found that many areas in the Caribbean, Bahamas, Florida, etc. have this same problem (Theile 2001; Hesse 1979; Wilson et al. 2005). Even though Jamaica is a part of CITES, more regulations are placed on the larger companies and few on the locals that fish in the area. Due to the lack of monitoring these fisherman can collect and harvest as much as they want and any size that they want. If this continues to happen then the population of S. gigas will

Strombus gigas densities in Discovery Bay, Jamaica

KORALLION decline to the point where the rate of population growth will become negative. In previous studies it was shown that if there were too few conchs within 10,000 m2 then they would not be able to find each other to reproduce (Harborne et al. 2006). It was found that in the Bahamas if there were less than 56 S. gigas per hectare, mating would not occur in open sandy bottom areas. But if there were less than 48 S. gigas per hectare, spawning would never occur (Harborne et al. 2006). Future studies Future studies that could be conducted are looking at the different fish that would colonize in Discovery Bay if a collection of S. gigas shells were placed with their openings up in the water column. Also to do more thorough sampling of S. gigas it would be beneficial to systematically go through the lagoon and grass beds to see if there are more younger juveniles living there. This could be done by dividing the area into 1 x 1 km2 areas and tow divers using a boat to cover more area (Stoner et al. 1996). ACKNOWLEDGMENTS The author would like to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. Erin Burge, Assistant Professor of Marine Science, Coastal Carolina University, Erin Cziraki, Scientific Dive Safety Officer Coastal Carolina University, and everyone in the MSCI 477 Ecology of Coral Reefs who contributed to the completion of this study. REFERENCES Appeldoorn RS (1988) Age determination, growth, mortality, and age of first reproduction in adult Queen Conch, Strombus gigas, off Puerto Rico. Fisheries Research 6: 363-378. Berg CJ (1976) Growth of the queen conch Strombus gigas, with a discussion of the practicality of its mariculture. Marine Biology 34: 191-199. Boettcher AA, Targett NM (1996) Induction of metamorphosis in Queen Conch, Strombus gigas Linnaeus, larvae by cues associated with red algae from their nursery grounds. Journal of Experimental Marine Biology and Ecology 196: 29-52. Collins PM (2007) Age-specific habitat preference by the Queen Conch, Strombus gigas, at Little Cayman Island. In: Peart FEDR, Barrow SELL, Collins SEPM, Harrison T, Marlow JA, Mayer ZA (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire. Collins PM, Harrison T (2007) Population structure and size distribution of Queen Conch in Grape Tree Bay, Little Cayman Island. In: Peart FEDR, Barrow SELL, Collins

SEPM, Harrison T, Marlow JA, Mayer ZA (eds) Dartmouth Studies in Tropical Ecology, Department of Biological Sciences, Dartmouth College, Hanover, New Hampshire. Harborne AR (2006) The functional value of Caribbean coral reef, seagrass and mangrove habitats to ecosystem processes. Advances in Marine Biology 50: 110-113. Hesse KO (1979) Movement and Migration of the Queen Conch, Strombus gigas, in the Turks and Caicos Islands. Bulletin of Marine Science 29(3): 303 - 311. McCarthy K (2007) A Review of Queen Conch (Strombus gigas) Life-history. National Marine Fisheries Service, Southeast Fisheries Science Center, Sustainable Fisheries Division, 75 Virginia Beach Drive, Miami, FL, 331491099, Kevin.J.McCarthy@noaa.gov 8. Randall JE (1964) Contributions to the Biology of the Queen Conch, Strombus gigas. Bulletin of Marine Science 14: 246 - 295. Stoner AW, Lally J (1994) High-density aggregation in queen conch Strombus gigas: formation, patterns, and ecological significance. Marine Ecology Progress Series 106: 73-84. Stoner AW, Lipcius RN, Marshall LS Jr, Bardales AT (1988) Synchronous emergence and mass migration in juvenile Queen Conch. Marine Ecology Progress Series 49: 51-55. Stoner AW, Pitts PA, Armstrong RA (1996) Interaction of physical and biological factors in the large-scale distribution of juvenile Queen Conch in seagrass meadows. Bulletin of Marine Science 58: 217-233. Theile S (2001) Queen Conch fisheries and their management in the Caribbean. Traffic Europe. Toller W, Lewis K.A (2003) U.S.V.I. Animal Fact Sheet #19 Queen Conch, Strombus gigas. Department of Planning and Natural Resources Dividion of Fish and Wildlife 1-2. Wilson SK, Sato SS (2005) Discarded queen conch (Strombus gigas) shells as shelter sites for fish. Marine Biology 147: 179 - 188.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

The effects of Diadema antillarum on macroalgae coverage along the forereef of Discovery Bay, Jamaica Katherine R. Podmore Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527

Abstract â&#x20AC;&#x201D; Macroalgae coverage has been linked to Diadema antillarum population densities such that a top down control by Diadema occurs. Since a mass mortality of the urchins occurred in the early 1980s, the reef has become more algal dominated instead of coral. This study observed the total percent macroalgal coverage along the fore reef of Discovery Bay, Jamaica in May 2010. This study showed a strong inverse relationship between urchin density and algal coverage. The data showed the Diadema zone to be located between 1.8 and 8 meters with some also located up to 0.6 meters. Algal species variability was less in highly dense urchin areas. Outside of this zone algae cover is much higher, which leads to the theory that the reefs are more algae than coral covered. Keywordsâ&#x20AC;&#x201D;Diadema antillarum, macroalgae, Discovery

Bay, Jamaica, population, herbivore, grazer INTRODUCTION

ACROALGAE dominate the coral reefs off Jamaica, but most of it comes from the decrease in the sea urchin Diadema antillarum and loss of major coral substrates. Macroalgae are algae that can be seen with the naked eye. They can be broken into three large color groups of Chlorophyta (green algae), Phaeophyta (brown algae), and Rhodophyta (red algae) (Sheppard et al. 2009). Green algae contain chlorophyll, which gives it the green color. Differing species require different habitats. Some prefer rocky environments, such as Dictyota spp., while others prefer sandy or protected areas, such as Caulerpa sp. or Udotea sp. (Human and Deloach, 2008). The brown algae contain fucoxanthin, which is a brown pigment. They have lower populations in tropical waters compared to that of temperate waters. The red algae are the largest group, but less is known about them. They contain a pigment called phycoerythrin, which, in large amounts, may appear brownish in color. The red algae help to form reef crests and calcareous plates on reef systems which help to build up the reef systems (Mumby and Green 2000). The red, brown, and green algae groups can also be characterized by their material, function, or form. These groups include fleshy macroalgae, calcareous algae, turf algae, branched corraline red algae and crustose coralline red algae (Mumby and Green 2000; Sheppard et al. 2009). The calcareous algae have a calcium carbonate frame and the turf algae are filamentous. The crustose coralline algae form crusts on substrata as well as cement coral fragments (Lapointe,1997; Mumby and Green 2000). The most abundant species of algae found in Discovery Bay are Dictyota sp., Halimeda sp., Sargassum sp., Galaxaura sp., and Lobophora This research was conducted as part of the Coastal Carolina University classes MSCI 477, Ecology of Coral Reefs, and MSCI 499, Directed Undergraduate Research, in Discovery Bay, Jamaica, 12-30 May 2010.

sp. (Hughes 1994; Lapointe et al. 1997; Solandt and Campbell 2001). Most macroalgae thrive in nutrient rich waters. The productivity of algal turfs, frondose macroalgae, and corraline algae have been shown to increase with increased nutrient availability, indicating bottom-up control by nutrient availability (Lapointe 1997). Marine pollution by human and animal waste, water runoff, pesticides and herbicides, and other human activities have increased nutrient abundances in water systems. The increase in nutrients has been shown to reduce animal grazing, which is causing a shift in reefs from coral to algal dominance (Lapointe 1997). Diadema antillarum are long spined sea urchins and can be found in shallow, rocky reef habitats (Alves, et al. 2003). These urchins play an important role in controlling algae coverage (Bak et al. 1984). They are active grazers and can open habitat to create a variance in herbivory. This increase in herbivory allows for expansion and more grazing from other organisms. Similar studies comparing algal coverage and Diadema population have shown that macroalgae density increased on the Caribbean reefs in the 1980s and 1990s. This is most likely due to the mass mortality of Diadema anitllarim and the decline in herbivory fish and coral cover in the early 1980s (Hughes 1994; Steneck and Dethier 1994; Lapointe et al. 1997; Aronson and Precht 2000). These decreases were in part caused by disease, hurricanes and overfishing (Hughes 1994; Steneck and Dethier 1994; Lapointe et al. 1997; Aronson and Precht 2000). Hurricane Allen, which crossed Discovery Bay in 1980, killed off most of the elkhorn and staghorn corals (Gayle and Woodley 1998). Coral cover declined from 50% to less than 5% in 1994 (Hughes 1994). According to Carpenter (1988), the mass mortality of Diadema killed 95-99% throughout the Caribbean and within five days of the mortality in St. Croix, U.S. Virgin Islands, the algal coverage increased by 20%. Once Diadema populations increased again in 1996 in St. Croix, the macroalgal population then began to decrease (Aronson and Precht 2000). The results from Aronson and Precht (2000) also showed that the abundance variability and inverse relationship between Diadema and macroalgae were consistent on the fore reef in Discovery Bay in the 4-6 m depth range. Below this depth, the population density of the urchins remained low while the algal coverage was high. Woodley (1999) concluded that in the 1990, at 5 m depth, fleshy macroalgae were abundant outside of Diadema patches, but near them the macroalgae were scarce while calcareous crustose algae were common. Although other control ideas relating to nutrient abundance and algal coverage have been hypothesized (Lapointe 1997), it is concluded that a top-down control of macroalgae by herbivory from Diadema is the most

Diadema antillarum effects on macroalgal cover in Discovery Bay, Jamaica

KORALLION

MATERIALS AND METHODS

RESULTS Diadema antillarum densities and abundance with depth Figure 1 shows the relationship between Diadema density and depth along the 9 north/south transects. The Diadema zone is shown to be between 2 meters and 8 meters in depth. The RÂ˛ value for the trendline is 0.0808. The overall depth range was 1.8 -11.0 meters.

12 10 Diadema Density

Common and abundant type in Discovery Bay (Aronson and Precht 2000, Hughes et al. 1987, Woodley 1999). This study observed macroalgal populations and distributions along the western fore reef in Discovery Bay, Jamaica in May 2010. The study identified and estimated the percent coverage of differing types of macroalgae and then compared their population to the abundance of Diadema, which was observed in a similar study that was conducted in the same location at the same time. It was hypothesized that areas of dense macroalgae would contain smaller amounts of Diadema and the patchy areas of Diadema would contain lesser amounts of algae with the exception of corraline algae, which is not tremendously effect by the Diadema (Carpenter 1998). It was also deduced that certain macroalgae preferred differing habitats so the abundance of algae would vary with location.

Study sites and geographic data

Data collection Algal concentrations were observed using 100 ft transects and a 1 mÂ˛ quadrat. Random samples were taken along 9 transect lines that ran perpendicular to shore and 6 that ran parallel to shore. Each transect was 100 feet long. Using a 1 mÂ˛ quadrat and a random generator, 6 to 11 random points along each parallel transect were used to take samples. In the field, six pictures were taken for each quadrat. The first was a picture of the placement along the transect and the last was an overhead shot while the middle four started in the top left quarter of the square and moved clockwise. The beginning and end of the transects were used to mark the beginning and end of each dive. The date and time were captured at the time the pictures were taken. For each quadrat the depth, total percent cover in the field, and number of Diadema were marked on the slate. Each quadrat was coded with the date, the number of the dive, the letter indicating the quadrat number (the first one on the transect would be A), and the depth. At the end of each dive, the data recorded on the slate was immediately recorded into a notebook once back at the dock. In the lab, the differing algae species were identified using the pictures taken in the field. For each sample, the algae type and its percent of coverage were organized into a table along with the total percent coverage for the entire sample.

6 4 R2 = 0.0808

2 0 0.0

4.0

8.0

12.0

Depth (m) A. Perpendicular

Diadema Density

This study was conducted along the western fore reef of Discovery Bay, Jamaica in May 2010. The bay is located on the northern shore Jamaica. The fore reef is separated into two parts by a shipping channel, which is used by a bauxite plant that has a port in the center of the bay. The bauxite plant is a source of nutrient and pollution runoff from the bauxite as well as the dispelled ballast water from the vessels. The study samples were taken at three different moorings; M1, Dancing Lady, and LTS; which are located west of the channel.

18 16 14 12 10 8

R2 = 0.0598

6 4 2 0 0

4 Depth (m)

B. Parallel Figure 1. Diadema density (# of individuals per m2) per sample with depth. A. represents perpendicular transects while B. represents parallel transects. Both densities were found by sampling randomly with a quadrat.

Macroalgal cover and distribution A linear regression test showed a strong significant difference between algal species for both parallel and perpendicular transects. The four most common species found in this study were Halimeda, Sargassum, Jania, and Dictyota sp. (Table 1). According to the overall data, there was no significance between species and depth. For the north/south transects, 57 quadrat samples were taken with an average total

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010

Table 1. Three most common species. A. represents the perpendicular transects in which 57 total quadrat samples were taken. B. represents the parallel transects in which 43 total quadrat samples were taken.

A. Groups

Dictyota Halimeda Jania Sargassum Total

Occurrence

Average % Cover

St. Dev

33.0

13.5

47 33 54 57

22.3 18.0 28.4

14.6 16.6 12.6

Occurrence

Average % Cover 27.6

St. Dev

20.7 26.8 26.3

11.1 18.5 11.5

Dictyota

Halimeda Jania Sargassum Total

23 31 36 43

90 80 70 60 R2 = 0.0017

50 40 30 20 10 0

B. Groups

100

% Macroalgae Cover

percent cover of 28.8 ± 32.2 %. Dictyota had the highest average coverage of 33.0 ± 13.5 % for the north/south transects and 27.6 ± 13.2 % for the east/west transects. Figure 2 represents the relationship between algal coverage and depth along the 9 north/south transects. The relationship between coverage and depth has an R² value of 0.1169. The overall depth range was 1.8 -11.0 meters.

13.2

0.0

2.0

4.0 Depth (m)

6.0

8.0

B. Parallel Figure 2. Total algal coverage per quadrat sample with depth for perpendicular (A) and parallel (B) transects. This figure shows the relationship between algal coverage and depth.

Algal cover and distribution in relation with D. antillarum densities Figure 3 indicates the Diadema density in relation to the total percent of macroalgal cover. Over all there is an inverse relation for both the perpendicular and parallel transects, in which Diadema coverage decreases as macroalgal coverage increases. 10 9 Diadema Density

Total % Algae Coverage/ m²

100 90 80 70 60

7 6 5 4 3

R2 = 0.2095

50 40

R2 = 0.1169

1 0 0

100

Total % Macroalgae Coverage

10 0

A. Perpendicular

0.0

4.0

8.0

12.0

Depth (m) A. Perpendicular

Diadema antillarum effects on macroalgal cover in Discovery Bay, Jamaica

KORALLION sandy areas. In future studies, rugosity should definitely be included in the field measurements to get a better understanding of the relationship. In conclusion, macroalgae coverage varies with depth and there is a direct relationship between coverage and urchin populations. Macroalgae was found at greater percentages and with more variety outside of Diadema patches. This indicates a top-down control of macroalgae by herbivory from Diadema. Slightly shallower patches of Diadema indiacate a slight change in herbivory and provide more grazing coverage. This in turns helps to control algae coverage.

Diadema Density

18 16 14 12 10

R2 = 0.3175

8 6 4 2

ACKNOWLEDGMENT

0 0

100

Total % Macroalgal Coverage B. Parallel Figure 3. Density of Diadema (Diadema per m2) by total per cent algal cover. This shows the relationship between the number of Diadema and macroalgal coverage. A represents perpendicular transects, B represents parallel transects

DISCUSSION This study supports previous conclusions that Diadema density affects macroalgal coverage. The Diadema zone was found to be between 1.8 and 8 meters along the north/south transects, which is congruent with Sellers (2009) of 2.0 to 8.0 meters. The east/west transects showed them to be located in 0.6 meters of water which indicates that they have moved shallower. This creates a change in herbivory by increasing grazing. Diadema open up habitat and create variety among organisms. This increased grazing helps to maintain the algal coverage. Morrison (1988) concluded that herbivory may control algal distribution upon depth. The common algal species are mostly consistant with previous studies in that Dictyota, Sargassum, and Halimeda sp. are abundant both in and out of the Diadema zone. The fact that these are so abundant is thought to occur due to the fact that Diadmea tend to graze more on the fleshy algae, such as Lobophora sp., and not the calcareous species (ex. Halimeda sp.) or those that contain metabolites which repel grazers, such as Dictyota or Sargassum sp. (Sammarco 1982; Sellers 2007; Solandt and Cambell 2001). The fact that these were some of the most abundant species, but the fleshier algae were not, correspond with previous findings. With the increase in grazing by Diadema, their preferred food type, though they usually eat whatever is in their habitat, would be in low supply compared to other species (Jackson and Sheldon 1994; Sammarco 1982). There was also less variety of algae inside the Diadema zone which could indicate a likeness to specific species. Some rugosity measurements were taken in a similar study about Diadema density. There was roughly an r² value of 0.4 in relation to Diadema population along the transect. The type of habitat and rugosity did play a role in algal coverage and urchin density. When there were more niches or tall structures, the urchins were able to hide within the structure. There was also more surface area for the algae to cover. Less urchins and less algal coverage were found in

The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. Erin Cziraki, Scientific Dive Safety Officer, Coastal Carolina University and Erin Burge, Coastal Carolina University, contributed to the completion of this study. REFERENCES Alves F, Chícharo L, Serrao E, Abreu A. (2003) Grazing by Diadema antillarum (Philippi) upon algal communities on rocky substrates. Sci Mar 67:307-311. Aronson RB, Precht WF (2000) Herbivory and algal dynamics on the coral reef at Discovery Bay, Jamaica. Limnology and Oceanography 45: 251-255. Bak RPM, Carpay MJE, deRuyter van Steveninck ED (1984) Densities of the sea urchin Diadema antillarum before and after mass mortalitlie on the coral reefs of Curacao. Marine Ecology Progress Series 17: 105-108. Carpenter RC, (1988) Mass mortality of a Caribbean Sea Urchin: immediate effects on community metabolism and other herbivores. Proceedings of the National Academy of Sciences of the United States of America 85:511-514 Gayle PMH, Woodley JD (1998) Discovery Bay, Jamaica. In: Kjerfve B (ed) CARICOMP - Caribbean coral reef, seagrass and mangrove sites. UNESCO, Paris : 17-33. Hughes TP, Reed DC, Boyle MJ (1987) Herbivory on coral reefs: community structure following mass mortalities of sea-urchins. Journal of Experimental Marine Biology and Ecology 113: 39–59. Hughes TP (1994) Catastrophes, phase shifts, and large-scale degradation of a Caribbean coral reef. Science: New Series 265(5178):1547-1551. Humann P, DeLoache N (2002) The Reef Set: Reef Coral. New World Publications. Jackson J, Sheldon P (1994) Constancy and change of life in the sea. Philosophical Transactions: Biological Sciences 344(1307): 55-60.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010 Lapointe BE (1997) Nutrient thresholds for bottom-up control for macroalgal blooms on coral reefs in Jamaica and Southeast Florida. Limnology and Oceanography 42(5.2):1119-1131. Lapointe BE, Littler MM, Littler DS (1997) Macroalgal overgrowth of the fringing coral reefs at Discovery Bay, Jamaica: bottom-up versus top-down control. Proceedings of the 8th International Coral Reef Symposium 1:927-932. Morrison D (1988) Comparing fish and sea urchin grazing in shallow and deeper water coral reef algal communities. Ecology 69(5):1367-1382. Mumby P, Green E (2000) Mapping coral reefs and macroalgae part A & B. In: Green EP, Mumby PJ, Edwards AJ, Clark CD (eds) Remote sensing handbook for tropical coastal management. Sammarco PW (1982) Effects of grazing by Diadema antillarum Philippi (Echinodermata: Echinoidea) on algal diversity and community structure. Journal of Experimental Marine Biology and Ecology 65: 83-105. Sellers AJ, Casey LO, Burge EJ, Koepfler ET (2009) Population growth and distribution of Diadema antillarum at Discovery Bay, Jamaica. The Open Marine Biology Journal 3: 105-111. Sheppard CRC, Davy SK, Pilling GM (2009) The Biology of Coral Reefs, University Press, Oxford. Solandt JL, Campbell AC (2001) Macroalgal feeding characteristics of the sea urchin Diadema antillarum Philippi at Discovery Bay, Jamaica. Caribbean Journal of Science 37(3-4): 227-238. Steneck RS, Dethier MN (1994) A functional group approach to the structure of algal-dominated communities. Oikos 69:476-498. Woodley JD (1999) Sea-urchins exert top-down control of macroalgae on Jamaican coral reefs (1). Coral Reefs 18:192-192.

Diadema antillarum effects on macroalgal cover in Discovery Bay, Jamaica

KORALLION

Analysis of sediment grain size distribution with respect to depth of coral reef grooves in Discovery Bay, Jamaica Dana E. Putman Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract â&#x20AC;&#x201D; The coral reef spur and groove formation is an important structure to the coast of Discovery Bay, Jamaica because they act as a breaker for the land from the approaching waves. The spurs, which are areas of active coral growth, are separated by deep depressions that act like sediment traps called the grooves. In this study samples were collected in the coral reef grooves at three locations; Dancing Lady, LTS, and M1. At all three locations the grooves were found to have the majority of sediment decreasing in grain size as the depth increased. This conclusion was found by calculating the graphical mean of a cumulative percent curve. Sediment sorting was also found to be independent from depth and skewness was found to get more symmetrical at a depth of about 45ft. Keywords â&#x20AC;&#x201D; Sedimentology, spur and groove, Discovery Bay, Jamaica, depth, sorting, grain size, skewness.

INTRODUCTION ISCOVERY BAY,

Jamaica coral reefs are an example of a carbonate system which acts as a sink for reef derived and lagoonal carbonate sediments. Carbonate sediment can be produced by coral reef organisms; this includes skeletal organisms as well as algal groups. These algal groups actually secrete carbonate within their tissue structures, and then they are released into the sediment. One study that focused on the forereef sediments in northern Jamaica concluded that sediment assemblages shift following changes in the coral reef community structure. Among others, some causes of these shifts were linked to severe hurricane damage, reduced herbivore abundance, and coral bleaching (Perry et al. 2006). In Jamaica bauxite rock was discovered above the carbonate rocks, therefore the bay has also been considered a sink for bauxite sediments. One source of the bauxite sediment is due to the loading and unloading of boats in the terminal that was constructed at Discovery Bay (Perry et al. 2006). Perry et al. (2006) also reported that bauxite has accumulated along the southern portion of the bay, showing that 35% of the weight of non-carbonate sediments made up surfical sediment samples in the bay. The bauxite accumulation can be visually observed in sediment cores because it has a distinct red-brown color. About one third of tropical coasts are made up of carbonate substrates (Spencer and Viles 2000). Coral reefs environments in particular are seen to convert dissolved calcium carbonate ions into insoluble calcite and aragonite calcium carbonate. Because of the large amounts of calcium carbonate that is secreted and accumulated, the complex ecosystems of coral reefs are formed (Goreau and Goreau 1973). Typical features that are seen on the windward side

of coral reefs are spurs and grooves, which run parallel to each other and form at the angle that the waves are approaching the reef (Hall 1999). The spurs are sites for active growing corals and can range from being found at sea level all the way down to 45 meters (m) deep. They also range in a variety of size. They can be anywhere from 8 - 65 m in width, 10 m in height and 70 m in width (Wood and Oppenheimer 2000). Coral reefs do not grow well in areas with high sedimentation; one reason for this is that the suspended sediments lower light availability (Rogers 1990). The spurs are then separated by the grooves which help to filter out the sediment. Skeletal fragments and other shell fragments of benthic organisms are found to be trapped in these grooves along with sediment. In addition, reefs are able to generate enough sediment that has a volume which at least equals their own growth (Acevedo et al. 1989). Therefore it is important to analyze the grain size of a sample in order to determine things such as sediment transport history, or how the sediment was deposited (Blott and Pye 2001). Grooves are created by the channelized flow of the water due to the coral reef growth on the spurs. The channelized flow causes turbulence which in turn erodes away sediment and produces the grooves (Wood and Oppenheimer 2000). Jamaica generally has irregular tides, and occur only once a day. The tides range in height from about 20 centimeters (cm) to 36 cm. A defined westward current is observed at both the northern and southern coasts of the island and becomes more pronounced between April and December, which is the trade wind season (Goreau 1959). It was concluded that coral reefs in the Caribbean-Atlantic region are affected by physical processes (Roberts et al. 1992). In the study it was observed that spur and groove orientations reflected any changes in the wave direction as they refracted over the reef shelf. The size and depth of the waves also were found to affect the coral reefs. Breaking, turbulence and friction of a shallow wave all affect the coral reef. These processes produce a current that transport sediment towards the lagoon. This for example influences the fluid flow and diageneses, which is any changes that occur to sediment after it has been deposited, within the coral reef community. Waves with low speeds, on the other hand, also affect coral reef communities because they are responsible for transferring larvae and fine sediment out of the reef-lagoon system (Robert et al. 1992). In a study done in the Indian Ocean on the La Saline fringing reef, coarse to medium grained sands were found in reef flats, which were subjected to higher wave energy, and very fine sands or coarse gravels were found in the back-reef, which is deeper and had lower water energy (Chazottes et al. 2008). Waves and tides, however, are not the only factors that affect coral reefs. Sediment deposition rates are strongly

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. influenced by the particle breakdown by eroding organisms. Although skeletons from certain species also contribute to sediment production, they are considered negligible when compared to the amount of sediment introduced to the system by bioerosion (Chazottes et al. 2008). Grazing from a species is one way grain size distribution is affected. For example, areas with species such as the sea urchin, which use their spines to dig burrows into hard rock, or the parrot fish, which use their beaks to scrape at corals as one way to eat, were found to have coarser sediments than environments with minor grazing activity (Chazottes et al. 2008). The present study was conducted in Discovery Bay, Jamaica on May 13th, 2010. The purpose of this study was to compare land derived sediment grain size and sorting distributed along the coral reef grooves. It was hypothesized that sediment grain size would be finer and well sorted in samples that were collected at sites deeper in the groove, in comparison to the coarser grain size and more poorly sorted sediment samples that were collected at the shallower sites in the groove, with higher energy. MATERIALS AND METHODS Study sites and geographic data Discovery Bay is located on northern coast of Jamaica. It sits near the western center coast of the island at 18°28’00"N, 77°24’30"W (Gayle and Woodley 1998). The weather of the northern coast is mostly dominated by northeasterly tradewinds, and a mixed tidal regime which has currents that are mostly wind driven. Discovery Bay itself is almost completely cut off from the open ocean by a fringing reef (Figure 1). The crest of the fringing reef breaks the surface of the water on the western side of the bay, but is under the surface on the eastern half. Between these two sections, a channel was built in 1964 (120 m wide and 12 m deep) in order for boats to travel in and out of the bay (Gayle and Woodley 1998). Field Methods Prior to entering the western forereef to collect surficial sediment samples in the coral reef grooves, 15 Ziploc bags were placed in a mesh bag, which was the same bag used to store sediment samples once collected in the grooves, along with a mechanical pencil. On waterproof paper, a pencil was used to write down sample numbers from 1 - 15. A total of three transect lines were laid lengthwise (starting at the shallowest part of the groove, and extending to the deepest part of the groove) near the center of three different grooves at three different dive sites. Surficial samples were collected throughout each of the grooves, attempting to collect only the surface most sediment at each site. The first transect line was laid in a groove located at Dancing Lady. The first sample in this groove was collected at a depth of 32 ft, where the groove began, and then samples continued to be collected at depths that increased by 5 feet. The final sample was collected at a depth of 58 ft, where the slope of the groove increased drastically. The depth that the sample was collected, determined using a Veo 100 Oceanic dive

Figure 2. Coral reef zonation off the coast of Discovery Bay, Jamaica. Coral reefs grow on the parallel spurs which are separated by deep depressions, grooves (Gayle and Woodley 1998).

computer, as well as the distance from the top of the groove, which was found using the transect line, was recorded in Table 1. The second transect line was laid in a groove to the west of the main groove and a site called LTS, and the third transect line was laid in a groove to the east of the first groove at a site called M1. In the remaining two grooves fewer surficial samples were collected in order to determine if a similar tend occurred in each groove regardless of its distance from the channel. At LTS a total of four samples were collected. The first was collected at a depth of 56 ft, the second was collected at 45 ft (about half way through the groove), the third was collected at a depth of 38 ft (which was the area of the groove right before it split into two different channels), and the final sample was collected at a depth of 31 ft (which was the depth were the groove began). At the final site, M1, a total of three samples were collected. One was collected at the top of the grooves, one in the middle, and the final was collected near the bottom of the grooves at about 60 ft. Once the sediment was collected in the bag, the depth and the distance from the top of the groove that the sample was collected was recorded using a dive slate. Then according to which sample it was, the number was ripped from the waterproof paper and placed inside the bag with the sediment in order to keep the samples labeled. No specific amount of sediment was collected at each site, because the samples were later weighed in the lab using an analytical scale. However, enough sediment was collected to fill the entire bag of a snack sized Ziploc bag, in order to assure there to be enough sediment to not only use in the lab, but also to be saved as a archive for later research. Lab Methods Tinfoil was used to make small boats in order to dry the sediment in. About half of each sample bag was spread throughout each tinfoil boat in order to form a thin layer. Each spread out sample was then placed in an oven set at 125 o C to dry for at least 15 hours. After the samples were dry, about 50 grams of each sample were weighed out. In

Sediment grain sizes in coral reef grooves in Discovery Bay, Jamaica

KORALLION Table 2. Sample Locations. At each sampling site the depth and distance from the top of the groove that each sample was collected at were recorded. Distance from the top of the groove was not collected for samples at LTS and M1 because only the change in depth was analyzed at these locations.

Site 1: Dancing Lady Sample 1 Sample 2 Sample 3 Sample 4 Sample 5 Sample 6 Sample 7 Site 2: LTS Sample 1 Sample 2 Sample 3 Sample 4 Site 3: M1 Sample 1 Sample 2 Sample 3 Sample 4

Distance 0 ft 51 ft, 11 in 100 ft 128 ft, 1 in 98 ft, 5 in 243 ft, 10 in 251 ft, 8 in

Depth (ft) 32 37 40 42 47 52 58

56 45 38 31

some cases there was less than 50 grams of sediment that was dried. In these cases the weight was still recorded in order to calculate the percent of each grain size present in each sample. Then a 63 micron (4 phi) sieve was used to sieve each sample. It was assumed that the grain size of mud was smaller than that of salt; therefore by sieving the sample the mud fraction was able to be determined. After the mud fraction was determined the remaining sediment was washed using tap water in order to wash away any salt. After the samples were washed, they were placed back in the oven for another 15 hours to dry again. Once completely dry, each sample was sieved for a minute and a half from a range of 1 to 4 phi, and data was collected and recorded for every 0.5 phi. After all the data was collected and recorded, the mean grain size and standard deviation was calculated for each sample in order to analyze each samples. Analysis Graphic mean, inclusive graphic standard deviation (IGSD) and inclusive graphic skewness (IGS) were determined by constructing individual cumulative weight percent curves for each sample collected. Folk and Ward (1957) and Boggs (1995) determined three equations for the calculations of these three types of data and the following were used for this research: (1) Graphical Mean = (Ȉ16+ Ȉ50+ Ȉ84) / 3

(2) IGSD = [(Ȉ84- Ȉ16) / 4] - [(Ȉ95- Ȉ5) / 6.6]

(3) IGS= [(Ȉ84- + Ȉ16-2 Ȉ50) / 2(Ȉ84- Ȉ16)] + [(Ȉ95+ Ȉ5-2 Ȉ50) / 2(Ȉ95- Ȉ5)] 50

RESULTS Graphical Mean Equation 1 was used to determine the graphical mean grain size for each sample. The sample that was collected at a depth of 40 feet was found to have a mean grain size of 0.4 phi, which was much finer that the mean grain size calculated at 42 ft which was found to be -0.3 phi. The mean grain size that was calculated for each sample can be seen in Figure 2. In the figure a positive trend is observed among the data. As the depth increased, the majority of the samples increased in phi size, or in other words, had a finer grain size. With an exception at depths of 40 ft and 42 ft, showing that areas of the groove can have different patches of sediment grain size.

Figure 3. Average Grain Size. Mean grain size of samples from Dancing Lady in respect to depth variation in the coral reef groove.

Equation 1 was also used to determine the graphical mean for the samples collected at LTS. At LTS samples were found to have a similar trend to those found at Dancing Lady, with the exception of the sample collected at a depth of 31 ft. At this depth the sediment was found to have a grain size with a phi size of 2.2 showing that at the shallowest depth the sediment was the finest. However, after this point, a similar positive trend is observed and shows that as the depth increased, the sediment became finer (Figure 3). The graphical mean was also calculated for samples collected at M1. At this site a positive trend was observed among the mean grain size and depth. The mean grain size of the sample collected at 38 ft is the finest of the samples collected in this site. However, when factoring in the error that may have occurred while analyzing, an increase in phi size is still observed with increasing depth (Figure 3). When comparing the mean grain sizes of samples at different sites to each other a very similar trend is seen at and deeper than 45 ft. If the sample collected at M1 at 38 ft was looked at while considering error, this trend can be seen even shallower at about 38 ft. Samples collected at the shallowest part of all the grooves vary in phi size, and all of them don’t follow the same trend that is seen throughout the rest of the groove. Sorting Equation 2 was used to calculate the IGSD. The values that were calculated were compared to a verbal term used by Boggs (1995). When comparing the types of sorting for each sample it was observed that depth really had no effect on the sorting. This observation was seen at all three sampling

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. sites. All samples were either moderately well sorted or moderately sorted. The variation in the IGSD values among all samples collected over each site was only 0.4 showing that no variation was observed in respect to depth.

Figure 4. Mean Grain Size Comparison. The mean grain size was found graphically for individual samples found at each site. Among all the samples, only the samples that were collected at similar depths were graphed.

Skewness Common skewness results were observed among all samples collected at all sites. In shallow depths samples tended to be more coarsely skewed and as the depth increased the sample became more symmetrically skewed. This showed that as the depth increased grain size became more evenly distributed among each sample. DISCUSSION Mean grain size was originally hypothesized to be coarse at the shallow depths of the groove and then become finer as the depth increased. In this study it was found to be the opposite of this original thought. There are a couple factors that can explain this. The initial hypothesis was based off the thought that the grooves began at a depth of zero. However it was determined in the study that the grooves donâ&#x20AC;&#x2122;t begin to for until a depth of about 30 - 32 ft. Because of this there is not direct interaction between the breaking waves and the sediment in the grooves. However, waves still may have an effect on the sedimentology of the grooves. A wave approaches the forereef at an angle, and once the wave breaks the pressure of the water retreating from the reef is what pulls the sediment seaward (Absi 2010). However, with the grooves starting at about 30 ft, this retreating pressure is neutralized by the reef crest; therefore the groove is not affected by this pressure. As the waves are approaching the forereef it pushes the finer sediment up the groove, and without the effect of the outgoing pressure, the sediment is just deposited. For the most part all the samples are moderately to well sorted. This shows that the chance of over erosion being a problem is very low because the amount of fine sediment in comparison to coarse sediment is about equal (Anthony and Hequette 2007). Waves may not be the only factor affecting the sedimentology of the coral reef grooves. For example, when sea urchins eat they ingest not only loose sediment that is trapped in the algae, but they also scrape the surfaces of dead

coral (Carreiro-Silva and McClanahan 2001; Alves et al. 2003). This shows that bioerosion is another factor affecting the sedimentology of the reef. Areas may have finer sand particles present that have a higher abundance of sea urchins bioeroding while feeding. In some areas urchins can be responsible for about 80% of the total bioerosion and on the other hand fishes, such as the parrot fish, are highly responsible in other areas (Alwany et al. 2009). On the forereef at Discovery Bay, both species are present and are responsible for the sedimentology of the reef. This could be the explanation for the varying results observed in the samples collected at 31 ft. These samples were collected in a narrow channel that began to form the groove and the site was surrounded by corals on three sides. Because of this, these sites may have acted as a trap for the sediment being that it was so enclosed that the waves couldnâ&#x20AC;&#x2122;t act as a factor on the sediment populations. Because of this, sediment that was analyzed may have just been products of bioerosion from urchins and fishes. There are some factors that may have affected the final results of the study. First, surficial sediment was not the only sediment that was collected at each site. This was due to the surge then was present during the collection of samples which was moving the sediment slightly. Another factor that may have affected the result was that while sieving, sediment was getting trapped in the sieve and not being factored into the results. It seemed that more sediment was getting trapped in the finer sieves than in the sieves that were a smaller phi size. Also, the proper equipment needed to determine mud fragments was not available at the Marine Lab in Discovery Bay, Jamaica. Therefore the method used in this research in order to determine the mud fragment may not be as accurate. There is an ongoing debate about whether grain size data alone is a reliable source for interpreting an environment, or whether the environment alone must be observed in order to determine depositional processes (Orpin and Woolfe 1999). Bases off the results from this study, an environment observation would be useful in order to determine whether the waves were the influencing factor or bioerosion on the sedimentology of the grooves. The research done in this study can be used as a basis for future studies. To the west of the research done in this study a road was removed near another coral reef, and to the east of the study site a hotel was just built. In a future study, similar methods could be used at these two sites in order to look at the different effects these changes have on the sedimentology of these reefs. During this year the channel is going to be dredged. After the dredging the same procedure that was performed in this study can be repeated in order to see how the channel affected the sedimentology of the Discovery Bay forereef. Along with looking at sediment sorting, the composition of the sediment can also be looked at in order to see the change in carbonate to terrigenous sediment ratio. In a past study, researcher looked at the amount of suspended particles in the water column. They found that the amount of suspended particles increases from reef to land (Jouon et al. 2008). In the future this study can be performed in a similar way, and concentrating on the suspended

Sediment grain sizes in coral reef grooves in Discovery Bay, Jamaica

KORALLION particles in the water column and determining exactly what direction the net flow of sediment is. ACKNOWLEDGMENT Special thanks to the staff of the Discovery Bay Marine Laboratory for the accommodations, equipment, and support during the duration of this research. Ronald Cash, Coastal Carolina University, contributed to the collection and evaluation of samples in order for this research to be completed. REFERENCES Absi R (2010) Concentration profiles for fine and coarse previous sediments suspended by previous waves over ripples: an analytical study with the 1-DV gradient diffusion model. Advances in Water Resources 33(4): 411–418. Acevedo R, Morelock J, Olivieri RA (1989) Modification of coral reef zonation by terrigenous sediment stress. Palaios 4: 92-100. Alves F, Chícharo L, Serrao E, Abreu A (2003) Grazing by Diadema antillarum (Philippi) upon algal communities on rocky substrates. Marine Science 67: 307-311. Anthony EJ, Hequette A (2007) The grain-size characterization of coastal sand from the Somme Estuary to Belgium: sediment sorting processes and mixing in a tide- and storm-dominated setting. Sedimentary Geology 202(3): 369-382. Alwany MA, Thaler E, Stachowitsch M (2009) Parrotfish bioerosion on Egyptian Red Sea reefs. Journal of Experimental Marine Biology and Ecology 371(2): 170176. Boggs S (1995) Principles of sedimentology and stratigraphy. 2nd ed. Englewood Cliffs, N.J.: Prentice Hall. Blott SJ, Pye K (2001) Gradistat: A grain size distribution and statistics package for the analysis of unconsolidated sediments. Earth Surface and Landforms 26: 1237-1248. Carreiro-Silva M, McClanahan TR (2001) Echinoid Bioerosion and herbivory on Kenyan coral reefs: the role of protection from fishing. Journal of Experimental Marine Biology and Ecology 262(2): 133 -153. Chazottes V, Reijmer JJG, and Cordier E (2010) Sediment characteristics in reef areas influenced by eutrophication-related alterations of benthic communities and bioerosion processes. Marine Geology 250(1-2): 114-127. Folk RL, Ward WC (1957) Brazos River Bar: A study in the significance of grain size parameters. Journal of Sedimentary Petrology 27: 3-26. 52

Gayle PMH, Woodley JD (1998) Discovery Bay, Jamaica. CARICOMP - Caribbean coral reef, seagrass and mangrove sites. UNESCO 17- 33. Goreau TF (2010) The ecology of Jamaican coral reefs I. Species Composition and Zonation. Ecology 40: 67-90. Goreau TF, Goreau NI (1973) Coral reef project papers in memory of Dr. Thomas F. Goreau. The Ecology of Jamaican Coral Reefs. II. Geomorphology, Zonation, and Sedimentary Phases. Bulletin of Marine Science 23: 399-464. Hall DB (1999) The geomorphic evolution of slopes and sediment chutes on forereefs. Geomorphology 27(3-4): 257-278. Jouon A, Sylvain O, Pascal D, Lefebvre JP, Fernandez JM, Mari X, Fridefond JM (2008) Spatio-temporal variability in suspended particulate matter concentration and the role of aggregation on size distribution in Sylvain coral reef lagoon. Marine Geology 256(1-4): 3648. Orpin AR, Woolfe KJ (1999) Unmixing relationships as a method of deriving a semi-quantitative terrigenous sediment budget, Central Great Barrier Reef Lagoon, Australia. Sedimentary Geology 129(1-2): 25-35. Perry CT, Taylor KG, Machent PG (2006) Temporal shifts in reef lagoon sediment composition, Discovery Bay, Jamaica. Estuarine, Coastal and Shelf Science 67(1-2): 133-144. Robert HH, Wilson PA, Lugo-Fernández A (1992) Biologic and geologic responses to physical processes: examples from modern reef systems of the Caribbean - Atlantic Region. Continental Shelf Research 12(7-8): 809-834. Rogers CS (1990) Responses of coral reefs and reef organisms to sedimentation. Marine Ecology Process Series 62: 185-202. Spencer T, Viles H (2002) Bioconstruction, bioerosion and disturbance on tropical coasts: coral reefs and rocky limestone shores. Geomorphology 48: 23-50. Wood R, Oppenheimer C (2000) Spur and groove morphology from a late Devonian reef. Sedimentary Geology 133(3-4): 1851-1893.

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

Mangrove Forest Survey at Discovery Bay, Jamaica Amy Tyillian Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527 Abstract – Mangrove forests are common in Jamaica, but the forest in Discovery Bay still goes unrecognized. This survey was completed to provide general knowledge of the mangrove ecosystem in Discover Bay. It was found that the red mangroves were the most abundant species followed by the white mangrove. It was also found that the forest was not continuous along the coastline; the mangroves were in smaller groups. Keywords – Rhizophora mangle, Avicennia germinans, Laguncularia racemosa, Conocarpus erectus, mangroves, distribution, location, abundance, Discovery Bay, Jamaica

INTRODUCTION

are among the most unique, diverse and productive ecosystems. Mangroves are unique in that they can survive against exceptionally harsh environments, meaning they can survive changes in salinity, and water level during the tides. They are diverse in that they provide a habitat to both aquatic and terrestrial organisms. Mangroves are highly productive from a biological, physical, geomorphic and economic stance (Kathiresan and Bingham 2001). Mangrove-dominated ecosystems are typically located within 30 ̊ North and South of the equator. This is due to a strong correlation between mangroves and temperature, where the mean annual temperature is approximately 24 ̊C (Spalding 2001). Mangrove reproduction peaks in spring and early summer. The distribution of propagules primarily occurs in August and September (Rabinowitz 1978). Mangrove distribution and location is dependent on ocean currents, and low energy areas that tend to experience effects of tidal changes. Some examples of these areas include river banks, river deltas, and carbonate islands (Webber 2009). Mangroves grow in these areas because of the strong influence of water, nutrients, salinity, and soil type due to the changing tides (Spalding 1998). Mangroves are designed to survive in stressful environments. They can withstand a constant change in salinity, as well as anaerobic soils and times of flooded soil (Spalding 2001). In Discovery Bay, Jamaica, (18 ̊28’00”N, 77 ̊ 24’ 30” W) there are four naturally occurring species of mangroves; Rhizophora mangle, Avicennia germinans, Laguncularia racemosa, and Conocarpus erectus. These mangroves inhabit a limestone substrate, where there is little to no top soil. According to research completed by Gayle and Woodley (1998), the largest portion of the dissolved nutrients within Discovery Bay was provided by the mangrove forests (Gayle and Woodley 1998). As of 2005, the Food and Agriculture Organization of the United Nations does not recognize the mangrove forest in Discovery Bay (Forestry Department 2007). ANGROVE FORESTS

Rhizophora mangle, commonly known as the red mangrove, received its name due to the red color of the wood underneath the bark. The mangrove has stilt, or prop, roots which allow for gas exchange, since the actual roots of the mangrove are typically in anaerobic soils. The leaves are relatively large with rounded ends, and have a leathery texture. The leaves line the stem opposite of each other. The flowers have four pointed petals that are a pale yellow or cream color. The red mangrove bears seedlings that have a torpedo-like shape. Avicennia germinans, commonly known as black mangroves, are named for their dark color of trunks. The trunk is a dark color due to the presence of blue-green algae found among the trees. Black mangroves have a unique root system made up of pneumatophores, which are used more for gas exchange rather than for anchorage. The leaves tend to be narrower and aligned opposite of each other on the stem. In Jamaica, the black mangrove is the only mangrove species to have a buildup of salt crystals on the leaves. The mangrove bears oval shaped fruit, and flowers which have four petals that are white in color. Laguncularia racemosa, commonly known as the white mangrove, is named after the light color of its trunk. The white mangrove also has pneumatophores; although they are shorter and have a knob-like feature at the tip. The leaves are rounded and aligned oppositely on the pinkish color stem. An identifying feature for the leaves are the large salt glands that sit on the petiole. The white mangrove also bears small, white flowers. Finally, Conocarpus erectus, commonly known as button mangrove, are considered a semi-mangrove. This mangrove has no prop roots. The leaves are thin, elongated, and have three salt glands on the petiole. The leaves are also arranged so that no leaf is directly across from another. The flowers of the button mangroves grow in small clusters. Each species of mangrove has a preferred environment, even though they are located in basically the same area. Red mangroves tend to grow in areas that come in direct contact with the river, sea or lagoon. The black mangroves tend to grow behind the red mangroves, in saturated soils. In an idealistic world the white mangroves would grow directly behind the black mangroves, but this is not the case in Jamaica. White mangroves are found randomly dispersed throughout the red and black mangroves in areas of compacted soil (Webber 2009). Mangroves are vital to the coastlines they inhabit. Mangroves provide protection and stabilization of the coastlines from erosion. They enhance coastal waters by filtering runoff water and providing nutrients. Mangrove forests are an excellent support for coastal fisheries, providing a strong, healthy habitat for species of both terrestrial and aquatic life forms (Mumby 2004). A healthy

Mangrove survey in Discovery Bay, Jamaica

KORALLION mangrove ecosystem is important to support coastal fisheries in Jamaica. Human exploitation is causing a significant decrease in the abundance of mangroves all over the world (Kathiresan and Bingham 2001). Jamaica has lost approximately 30% of its mangroves (Forestry Department 2007). Mangroves are being harvested for fuel and timber, which in turn affects the fisheries (Spalding 2001). Studies have also shown that even though mangroves can withstand many harsh environments, they are sensitive to human impact such as pollution and oil spills (Kaly and Jones 1998). Side effects of negative stressors include mortality of the mangroves, and a reduction in the canopy cover (Department of Environmental and Resource Management 2009). These physical changes to the soil prevent a natural recovery of the mangroves. It is possible for mangroves to have natural recovery but it would be very slow (Kaly and Jones 1998). The data that was collected from the mangroves of Discovery Bay, Jamaica, will serve as a baseline to measure the change of this highly specialized ecosystem due to human exploitation. The mangrove site will be assessed to gain an understanding of the mangrove habitat in Discovery Bay, such that the abundance of each species and general location will be determined. An average basal area of each mangrove species will be calculated to gain an estimated developmental level for the ecosystem. A greater average basal area would suggest that there is a higher abundance of biomass, indicating a higher level of mangrove development (Department of Environmental and Resource Management 2009). The abundance of seedlings in the study site can give an approximation for the relative volume of seedlings. Although this will not be very helpful in this specific experiment, it is important to note that as seedling and sapling data is collected, the level of stress on the environment can be interpreted.

the mangrove at breast height. The basal area describes a cross-section of girth of the mangrove (Department of Environmental and Resource Management 2009).The location of each identified mangrove was also plotted using ARCGIS onto a diagram of Discovery Bay (Jamaican Forestry Department 1998). RESULTS The mangrove forest is separated into several different clusters, as shown by Figure 1 and their estimated area is shown by Figure 2. These clusters have no specific shape, size and are dispersed randomly along the coastline. Mangrove section 5 had the largest area of 892.25 m2, followed closely by mangrove section 2 (Figure 2). The smallest area was mangrove section 3 of approximately 100 m2. The combined total area equals 2202.76 m2.

MATERIALS AND METHODS A mangrove forest at Discovery Bay Marine Lab (DBML) in Jamaica was chosen for analysis on the density of the forest. The process began with delineating the forest area using a Magellan Triton 500 GPS to obtain the coordinates of the mangrove forest parameter. The delineation was completed by walking the parameter of the mangrove forest. Using ARCGIS, the coordinates for the parameter were mapped out. Then a grid layer measuring approximately 10 m x 10 m was layered over of the parameter map, so that random sample areas could be chosen. These plots designated areas where each mangrove was identified for species type and position; they were also measured for diameter at breast height (~1.3 m). Each plot received an estimated canopy cover percentage, according to Monitoring and Sampling Manual 2009. Seedlings and saplings were also analyzed for species type, position, and height within the 10 m x 10 m plots if there appeared to be less than 50 seedlings/saplings available (McGowan 2006). From the previously gathered data, the mangrove forest area and the relative density of each species were calculated. The average basal area was also calculated using the girth of

Figure 1. Mangrove Areas within Discovery Bay, Jamaica. This shows the mangrove forest is spilt into several clusters along the coastline. Each cluster has been designated a number starting with section 1 at the bottom right of the Figure 1, and moving left and upwards till section 5 has been reached. It is important to note that area 3 is exceptionally small relative to the other sections, so it cannot be easily seen in this figure. Also, the outlined box represents the apartment style dorms located at Discovery Bay Marine Lab.

the overall distribution of the red and white mangroves can be seen in Figure 3. The distribution of each species appears to be randomized, not setting any specific trends. A comparison can also be drawn from the abundance of each species. There is a distinct abundance of red mangroves compared to the white mangroves (Figure 4). The species ratio was also determined at this point to be five red

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

Figure 2. Area of each mangrove section in Discovery Bay, Jamaica. Figure 5. Average basal area for red and white mangroves in each mangrove section.

mangroves for every two white mangroves, reinforcing that red mangroves are in greater abundance. The average basal area of each mangrove species within each mangrove section is shown (Figure 5). Mangrove section 4 had the largest average red basal area of 270.11 cm2; section 5 had the largest white mangrove basal area of 703.33 cm2. Mangrove section 3 had the smallest average red basal area of 30.29 cm2, and both mangrove sections one and two did not contain any white mangroves.

Figure 3. Distribution of the red and white mangroves. The analyzed mangroves were plotted over the Jamaica mangrove area map.

Figure 6. Distribution of mangrove seedlings.

Figure 4. Count of each species. This graph shows total amount of red and white mangroves counted within Discovery Bay, Jamaica.

There were no saplings in all of the mangrove sections. Only red seedlings were found in mangrove sections 4 and 5. The average seedling height for the red mangrove seedlings for section four was 43.09cm, the highest average. The average seedling height for the red mangroves in section 5 was 23.71cm. There were no other species of mangrove seedlings in the studied sections. The distribution of the seedlings is shown in Figure 6.

Mangrove survey in Discovery Bay, Jamaica

KORALLION

Figure 7. Average seedling height for each mangrove section.

DISCUSSION The mangrove forest in Discovery Bay, Jamaica does not follow the typical continuous, layering protocol as other Jamaican mangrove forests do. The mangrove forest is in separate clusters along the coastline of Discovery Bay (Figure 1). The mangrove forest may be in these scattered clusters due to natural mortality and regeneration based on the availability of light and space (Alonhi 2002). It may also have to do with the abnormal limestone substrate, within which these mangroves are growing. It is possible that the tidal fluctuations are not reaching the limestone substrate in these empty areas. The mangroves found within these sections show no clear zones of species, as Webber (2009) had suggested would be found in an ideal world. The distribution of the red, black, white and button mangroves are scattered throughout the parameters. The red mangrove is in high abundance compared to other species, and the white mangrove population is sparse in comparison. It is important to note here that although black and button mangroves did not appear within the randomized sample areas, they were observed in the field during delineation. This supports Forestry Department (2007) saying that the majority of Jamaican mangrove forests are primarily made up of red mangroves, with smaller groups of black, white, and button mangroves. Another study completed by Asprey and Robbins (1953), corresponded in the poor zonation of species. This article also stated that zonation is strongly dependent on the tidal fluctuations, and Jamaica only has a fluctuation between 8 - 10 inches, over short periods of time (Asprey and Robbins 1953). The low abundance of seedlings/saplings is unusual to mangrove forests, as well as finding only red seedlings. There are several different studies that would suggest reasons for this low abundance. A study completed by Smith (1987) suggests that this low abundance is strongly correlated to predation of the propagules. Smith also found that the red propagules were the least preyed upon. This relates to this study, because even though different mangrove species were found in the area, only red seedlings were found. When these studies are related one can believe that the other species types were preyed upon during the propagules stage. It has also been suggested that the 56

propagules traveled farther distances in less dense mangrove forest (Komiyama et al. 1992). Likewise, if the forest was denser the propagules would settle before being able to disburse far distances. A different explanation is that the lack of seedlings/saplings, after the normal disbursement period, could indicate a rigid environment. Considering that the mangroves in Discovery Bay are growing on a limestone substrate with minimal to no soil, the propagules cannot always ground themselves into the sediment. This would prevent the growth of these mangroves (Rabinowitz 1978). Another observed factor related to a rigid environment is that there was a large abundance of trash in the mangrove ecosystem. The trash may be breaking and killing the seedlings/saplings. Once the propagules have been grounded, there are some factors affecting the growth and development. Light and space availability in the mangrove forest strongly affects the growth and development. The lighter, the better; seedlings have a very low tolerance for shade (Asprey 1953). Space availability is also crucial for growth of seedlings. The numbers of seedlings/saplings can be greatly swayed by local disturbances in the area, such as hurricanes and if any part of the forest is being mined for timber and construction (Department of Environmental and Resource Management 2009). The average basal area of the mangroves provides some insight to how productive the system is. A larger basal area indicates that there is more biomass produced, which therefore helps in determining the level of development. The increase in biomass from the mangroves is supported by other studies including Mumby (2004). A stronger baseline of data is needed to determine the level of development, but the gathered data is a starting point for interpretation. As data is collected over years, an increase in basal area would represent a continuation in growth; a decrease in basal area shows the result of disturbance (Department of Environmental and Resource Management 2009). Again this will be more help in future studies. A total estimated area was calculated so that a general idea as to how large the mangrove forest was could be obtained. The estimated average area is 2202.76 m2. The total area of all mangroves in Jamaica is equal to 7000 hectares (Choudhury 1997). The average area for Discovery Bay is exceptionally small compared to that of the total area of Jamaica. The estimated average area for Discovery Bay currently serves no other meanings, but it can also be used in future studies to determine growth rate, and other various numbers. A continuation of studies needs to be completed on the overall mangrove structure in Discovery Bay. It would be suggested to use modify this study in several ways, starting with using actual measurements of canopy cover, rather than an estimate based on the authors discretion. Another important variable would be to observe changes in mangrove height over long periods of time. These minor additions and adjustments to the study will provide a greater understanding of the state of health in these systems. It is important to have an understanding if the small ecosystem has chance at

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. survival, or if actions need to be taken to prevent the die out of mangroves in Discovery Bay. ACKNOWLEDGEMENTS The author would like to thank Discovery Bay Marine Lab and Coastal Carolina University MSCI 477 class of 2010 for all their help. REFERENCES Alongi D (2002) Present state and future of the worldâ&#x20AC;&#x2122;s mangrove forest. Environmental Conservation. Foundation for Environmental Conservation 29(3): 331349. Asprey G and Robbins R (1953) The vegetation of Jamaica. Ecological Monographs 23(4):359-412. Choudhury J (1997) Sustainable management of coastal mangrove forest development and social needs. Mangroves and Other Coastal Forests 6 (38.6).

Kaly UL, Jones GP (1998) Mangrove restoration: A potential tool for coastal management in tropical developing countries. Ambio 27: 656-661. Kathiresan K, Bingham B (2001) Biology of mangroves and mangrove ecosystems. Advances in Marine Biology. 40: 81-90. Komiyama A, Chimchome V, Kongsangchai J (1992) Dispersal patterns of mangrove propagules. Department of Forest Land Management. 57: 27-34. McGowan T (2006) An assessment of mangrove forest structure in the Las Perlas Islands, Panama. Thesis. Heriot-Watt University, Edinburgh 30-40. Mumby P, Edwards AJ, Arias-Gonzalez JE, Lindeman KC, Blackwell PG, Malgosia AG, Harborne AR, Pescod CL, Renken H, Wabnitz CCC, Llewellyn G (2004) Mangroves enhance the biomass of coral reef fish communities in the Caribbean. Letters to Nature. Nature Publishing Group. 427: 533-536.

Department of Environmental and Resource Management (2009) Monitoring and sampling manual. Environmental Protection Policy 1.

Rabinowitz D (1978) Dispersal properties of mangrove propagules. Biotropica 1(1):47-57.

Forestry Department (2007) Mangroves of North and Central America 1980-2005. Food and Agriculture Organization (FAO) of the United Nations.

Smith T III (1987) Seed predation in relation to tree dominance and distribution in mangrove forest. Ecology. 68(2): 266-273.

Gayle PMH, Woodley JD (1998) Discovery Bay, Jamaica. CARICOMP. Caribbean coral reef, sea grass and mangrove sites. UNESCO 17-33.

Spalding M (2001) Mangroves. Encyclopedia of Ocean Sciences. Second ed. Elsevier Ltd 496-504.

Hold B (2006) Guide to the mangroves of Florida. Florida Sea Grant Marine Extension Program. Zandt Marketing Services, Inc Jamaican Forestry Department (1998) Land and use/cover of Jamaican developed using the Landsat 5TM satellite Imagery. GIS Shapefile

Spalding M (1998) Biodiversity patterns in coral reefs and mangrove forests: Global and local scales. PhD Dissertation, University of Cambridge. Webber M (2009) Biodiversity of Jamaican Mangrove Areas. Thesis.

Mangrove survey in Discovery Bay, Jamaica

KORALLION

Reef fish survey and biodiversity of fish in Discovery Bay, Jamaica Nicholas Krichten Department of Marine Science, Coastal Carolina University, PO Box 261954, Conway, SC 29527

Abstract – The purpose of this project was to study the relative abundance and biodiversity of the fish located in Discovery Bay, Jamaica. This paper discusses the biodiversity of the species of fish observed, and is to be treated as a general survey of fish in the area. The general idea is that the waters of Jamaica are rich with many species of fish and in numbers of individuals. The reefs have high nutrient production and thus support a large community of organisms. The study looked at reefs made up mostly by algae, mixed and coral based. Keywords – coral reef, fish biodiversity, Discovery Bay, Jamaica

INTRODUCTION

is a comparison between the biodiversities of different reef locations while in the general area of Discovery Bay, Jamaica. The three diversities recorded in this survey are alpha diversity, beta diversity and gamma diversity. In this study, only beta diversity will be compared. The other two tests were completed and the results were recorded but were not used in this study. This study is on the comparison of different locations and not a comparison of one location to the whole area being studied. Studying the biodiversity is a way of looking at species richness at different locations and a comparison between the locations. Alpha diversity is a way of understanding the diversity of a species in a local area, not of a large area, which this study was based on. The alpha diversity, according to Zhuravlev (2005) is about how many individuals live in a specific location. For this study, looking at whole area is more important then the diversity of the individual sites itself. A study found that with increasing depth, diversity decreased but the number of rare species increased. This is observed that in the shallower waters close to shore 71 % of the species are referred to as common species but in the deeper depths 86 % of the species is explained by rare species. This applies to coral reefs but not necessarily to algae driven reefs like Discovery Bay. Discovery Bay is different in that the highest diversity is located in the sea urchin zone located near the reef crest. Several studies have been done that show areas controlled by sea urchins will have higher diversity then areas with out them, which is based off of the intermediate disturbance hypothesis. Beta diversity is the most important one to look at. The significance of how similar or how different two separate environments are, is profound. A returned value of one means the two locations are identical and a returned value of zero means the two locations are not similar at all. In the protection and conservation these values are what matters (Fontana et al 2008). For government agencies finding two locations that HIS STUDY

_______________________________________________________________ This research was conducted as part of the Coastal Carolina University classes MSCI 477, Ecology of Coral Reefs, and MSCI 499, Directed Undergraduate Research, in Discovery Bay, Jamaica, 12-30 May 2010.

return a value close to one make it easier to protect an endangered species that could reside at both locations or where a species can be relocated to if needed. At the same time this goes back to the question: Should we save many small locations that is high in different diversity or one large location with high diversity itself? The more different the two areas are the more likely they have rare and valuable species that need protected. The more similar the two communities the easier it is to replace a species that went extinct in the one area but not in another. While it is good for saving different locations with rare species, it is also a good tool to determine how healthy a reef is when comparing it to the “ideal” reef. When diversity is found at different locations in a larger area of ocean it is possible to compare all of the reefs to see which ones have similar fish and which ones are completely different. By comparing beta diversity of different areas around the same reef it is possible to tell what parts of the same reef are actually different micro reefs. It is then possible to compare the many dive sites that are geographically near each other but have different species. One of the simplest reasons for this difference is some locations are coral driven and others are algae driven. At several sites there was recorded both a coral and an algae zone that was controlled by sea urchins. Thus the idea of micro reefs is possible on a larger reef area. The greatest variable that affects beta diversity is the sampling area and how small of an area you end up using. At the same time, several samples at the same site will yield results closer to the actual conditions at that given location. The surface area needs to be large or the data can be incomplete for the rarer species. When a survey is being conducted it is possible to capture a “rare species” or a species that is found only in one particular location, and getting results for its diversity is hard to obtain. The rare species may be located at the sites but it is impossible to tell with it being a hard to find species (Fontana et al 2008). The test used to link species is the beta test given that is compares two different locations. It has been found that beta diversity has been used in literature since 1966 by McArthur. The Whittaker test is the ratio of gamma diversity over alpha diversity, which is another form of beta diversity. In this paper, the Whittaker will not be used, but instead the Sorensen test was used. The absence or presence of some accurate species count can lead to good data or useless data that scientists interpret as best as possible. To limit this fuzzy effect, several studies were done at the same site to improve the data’s reliability. Using these diversity tests, it is possible to compare different environments to compare if one species found at one location can be moved to a different location. The tests don’t necessary require a full inventory of the species that reside in an area but a random sample of those species (Fontana et al 2008). It is believed that a blind sampling of a location will provide

Reef fish biodiversity

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. enough data that will include most of the species that reside in that habit (Fontana et al 2008). The only real way to compensate for this error is to do the study many of times and with many trials it may be possible to observe all rare species. It is recorded that immigration can effect how diversity can be affected (Zhuravlev and Naimark 2005). It was noted that when comparing two locations they are similar to start out with or the data collected will be meaning less (Zhuravlev and Naimark 2005). When doing surveys for biodiversity, it is best to have many locations to compare then just a few (Zhuravlev and Naimark 2005). Gamma diversity is a way of comparing species that live in a similar area to the whole area (Fontana et al 2008). Gamma diversity is about total species richness in a large global area. The values returned for this data is not that reverent to this study because all of the locations surveyed are around Discovery Bay. The values were found for this study were recorded but will not be analyzed in this survey. Gamma diversity can be found by γ =S1+S2-C where both S’s are the species count at the two locations and C is the common species. Alpha diversity also recorded is found by α = γ / β where γ is gamma diversity value and β is beta diversity value. As mentioned before both alpha and gamma values were found but not being studied in this paper. A general study of a reef’s biodiversity is important for many reasons. The most obvious reason is that a healthy reef would be very diverse and support a large community of organisms. The intermediate disturbance hypothesis states that at intermediate disturbances their will be a high diversity. With that said reefs mostly made up of algae will be stable and have lower disturbance. A reef found with many herbivores will thus control algae and improve biodiversity. The reason why this is important to note is that Discovery Bay, Jamaica has low grazing from overfishing and sea urchin die out in resent times that the reef is slowly recovering from. In order to obtain an accurate diversity of an ecosystem one needs to first look at the environmental factors. This means the abiotic factors have to be accounted for. The change or evolution of an environment will cause a change in the organisms living in that environment. This skewing of the organisms to fit the individual niches of the ecosystems means reefs in similar conditions should be similar but that is not always the case. Small differences can have a profound change of both species richness and genetic flow. The depth of the reef is an important factor in what lives on or near the reef. The greatest modern change in species richness on a reef has to do with eco-management and marine wildlife parks. Some places, mainly industrial countries, protect species richness while poorer, developing countries take advantage of it. The choices of coral that make up a reef have an impact on who lives on that reef with them. In modern times, species diversity has been a major study to see what impact man has on the reef system as well as global warming. It has been recorded that it is possible to have a micro-reef or a patch of reef that doesn’t fit in with the rest for different unknown reasons (AriasGanzalez et al 2008). Species richness is a dependent variable on how much disturbance an environment has over a given period of time. If there is little disturbance then there will be few species, but those species will be mature and create a stable environment.

At the same time, too much disturbance and low diversity will accrue because few organisms will be able to live in those extremes. This lead to what is known as the intermediate disturbance hypothesis, which states an environment with moderate disturbances will have the highest diversity. At this point, competition will be at its maximum and more species will be able to survive. At intermediate disturbance, emigration and immigration will be high and a rapid change in genetic flow is possible. With that said, rapid evolution and extinction will also be possible due to intermediate disturbance. The intermediate disturbances can create a wide variety of ecological niches in a small area that allows for a high biodiversity to live in these niches (Aronson and Precht 1995). It is believed that species diversity will increase with depth up to maximum diversity and then decrease with increasing depths below that maximum. The peak diversity was found to be around six meters, where sunlight penetration starts to be reduced. The changes in depth cause a change in wavelength and a change in what phosynthetic organisms live at that depth. At peak intensity near the surface, the diversity of photosynthetic organisms is low because of the extreme conditions. The diversity thus does increase with depth so that it slowly reaches a stable environment with intermediate disturbances for maximum diversity. The higher diversities were observed due to more stable conditions then in the shallower, wave-driven reef areas. It was observed that the different genuses or families will be found in only a specific environmental gradient. With that said, some genuses are not present at different depths but similar genus’s take their spot instead (Guimaraens et al 1994). Measuring the diversity between terrestrial and aquatic ecosystems is different. Land-based ecosystems are easy to define and thus easy to measure diversity. On land it’s easy to divide the area up and easy to manage the boundaries. However, in the water, the boundaries can move, or not be easy to establish. The only time land diversities run into problems is when high trees are involved and the canopy layers skew the diversity results. It is easier to compare different habits if they are closer together. This is true for adjacent ecosystems that are closely related. It was found again, that human interactions with the environment have adverse effects on what species are present (Pineda and Halffier 2003). The purpose of this study was to find what effects humans have on the environment. The effects of man by run off has increased productivity in the way of nitrogen and phosphorus and can lead to a change in biodiversity based on a new ecosystem with high nutrient input. These areas affected by farmers’ run off have high productivity and a homogenous mixture of diversity (Thiere et al 2009). The Strong method was determined to be the best way of sampling and comparing data. It is possible to compare terrestrial and marine environments together to see if they correlate with each other. The goal of finding biodiversity is the change in diversity over time and how an ecosystem is evolving with time. The best way to obtain the data is to use simple random sampling so that the data is not skewed one way or the other by the researcher’s observations (Bankus et al. 2007). 59

KORALLION It is found that currently biodiversity is slowly decreasing. The purpose of this study is to determine the changes in biodiversity with time. In order for this to be a success the data would have to be collected over a length of time if not years. The two taxa of the marine communities that are affected the most are coral and fish. The other studies found that the diversity of fish is conserved and not changing as much as it would be expected. At the same time biodiversity richness gradients were observed and recorded in previous studies. These gradients are linked to longitude and latitude of the studies involved (Bellwood and Hughes, 2001). MATERIALS AND METHODS Study sites and geographic data This study was conducted from May 17 to May 26, 2010. The study was at several reefs locations around Discovery Bay. The reef sites used in this study are known locally as Dancing Lady (DL), Dairy Bull (Dairy Bull) East Back Reef (EBR), LTS, and M1. These studies were conducted at different times of day from the early morning to the afternoon. A total of sixteen surveys were done at the different sites: DL 6, DB 2, EBR 1, LTS 4 and M1 3. On a side note the second Dairy Bull dive was a tank dive along a 100m transects and the area around it. The data collected on this double dive will be used also for a different study of how Dairy Bull has changed over the years. The data collected in this fashion was used in this study and is considered more in depth and accurate then the other dives. The other data collected is reverent in that it was collected over several dives to record all possible species of fish present at each location. Data collection This study was done by collecting data by observation and was done by using the Reef.org visual identification study. Reef.org is an organization of divers doing surveys of reefs around the Gulf of Mexico and Caribbean Sea. The study was conducted over several days in Discovery Bay Jamaica. All known species of fish were surveyed and fish that could not be positively identified were not recorded to prevent bias of the study. All of these studies were conducted in less then 50ft of water. These studies were conducted using just a simple visual identification method. The data was collected while SCUBA diving and observing what fish are present visually. This was done by swimming above and observing below, as well as looking under the overhangs. Some of the studies included the algae zones and some of the studies were in the sea urchin zone at the sites. This was done to actually record the number of different fish species present at each site. The number of species present at each dive site will be recorded and analyzed for biodiversity. While the number of species is being recorded the abundance of each fish was also being recorded. The abundance being recorded was based on simple data collections of single, few (2-10), many (11-50) and abundant (50+). This data collected will not be analyzed in this paper but will help Reef.org in their future studies.

Analyses These numbers that were collected were analyzed for biodiversity. Biodiversity of the different dive sites was compared by using the beta test noted below. Where S1 and S2 are the two different species counted at the two sites and C is the common number of species between both sites being compared. The values being returned will be 0 to 1 with 1 being the most common and 0 being very different. The higher the number tells how similar the species are at the two locations. This project will use statistics to compare the locations. In this study each reef will be treated like an independent island. With that said the rules of island biogeography will then apply. The limitations that prevent this from being a perfect study are the exact areas of each reef and the distances will be estimated. The estimations will be done with how far one can swim on one SCUBA tank and what area that can be covered during this time. To perform an accurate test the exact areas of the reefs would need to be compared. All of the data collected will be used to compare the different areas and provide the useful data of this study. With out the statics and analysisâ&#x20AC;&#x2122;s the data collected would have no meaning and no baseline to compare different areas. Many more studies over the years will be needed to compare how the reef is changing with time. RESULTS The results of the study had some interesting findings. These results include calculated results as well as observed data. The data was collected on the dives both as counts and observational notes. The observational data in some cases of this study is more important then the number data collected. The most abundant fish found in the Discovery Bay reef system is the Blue Chromis. This fish was found in large schools with greater then twenty individuals each and greater then five schools per location. With that said at each site had well over a hundred individuals of this species that were observed in schools or as individuals. These fish were found at all depths and locations from coral to algae driven system. The next most abundant fish would be the striped parrotfish found at all locations in large schools. Though not nearly as abundant as the Blue Chomis, large schools were observed at all locations. Slightly less then a hundred individuals were found at all locations and were thus not recorded as abundant. One of the interesting findings was that squirrelfish populations were different at different locations. The most common squirrelfish was surprisingly not the one frequently observed around the reef. The most common squirrelfish was the longjaw Squirrelfish. The least common squirrelfish was the longspine which was found at the deeper depths hiding under coral overhangs. The rarest squirrelfish of all was the reef squirrelfish. It was only found as an individual on the Dairy Bull location. At the Dairy Bull location the most common squirrelfish was the dusky and was found in large numbers on this coral driven system. It was also noted that the dusky was observed as an individual at M1 and LTS. The

Reef fish biodiversity

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. DISCUSSION Overall this was a learning experience and uncovered some interesting data. The data collected in the beginning is incomplete because of the user knowing few species of fish. 60

Number of Species

dusky squirrelfish was only found in the coral driven area at those two locations also. The biodiversity tests were recorded in Table 1. The beta diversity data is the only data significant for this study. All of the beta diversity values are greater then .5 on a scale of 0 to 1. The highest value was of Dancing Lady and M1 was .83. The reef that was most different form all of the sites was the East Back Reef with the lowest values recoded. The reason for this site being most different may be from the fact that only one research dive was done at this location. The data collected for beta diversity is listed below in Figure 1.

0.9 10

Beta Diversity (%)

0.8 0.7

0.6

DL- LTS- DL- LTS- DL- LTS- DL- EBR- M1- M1- DL- DB- M1- LTS- DL- DB17 18 18 19 19 21 21 21 22-1 22-2 23 23 23 25 26 26

0.5 0.4

Location-Date

0.3

Figure 3. Locations and day in May 2010.

0.2 0.1

BR 1/ E M

D L/ EB R

L/ M D

S/ EB R LT

LT S/ M

S/ D L

B/ E D

D B/ M

D B/ LT

B/ D L

0.0

Locations

Figure 1. Beta diversity comparing of all dive sites Table 1. Beta, Gamma, and Alpha Diversity of all dive sites.

BETA GAMMA ALPHA

DB/LTS 0.6452 63 97.65

DB/DL 0.7451 64 85.89

DB/M1 0.7500 60 80

DB/EBR 0.5122 61 119.09

LTS/DL 0.7089 51 71.94

Number of Species

60 50 40 30 20 10 0 LTS

Dancing Lady

EBR

Dairy Bull

Common

Dive Site

Figure 2. The number of species observed at each location.

The best results were done with multiple studies of the same site over time to get an accurate picture of what species of fish are present. The number of dives to each location varied in that East Back Reef had one study. Dairy Bull had two studies with one being a very user intensive study that has the most accurate results. Dancing Lady had six surveys recorded on it. LTS had four studies and M1 had three studies. The results of each individual survey are recorded in Figure 3. The data was collected over several dives through out the research project. Each side had an uneven number of dives from what was requested to help out finish other studies done by other students.

As the number of dives increased, more species of fish were added the list of fish so in the end most of the common reef fish were known. The Dairy Bull study was the most reliable data collected in how it was collected. The Reef.org mini book was carried on this dive to do on site identification of new species not before recorded. At the same time a special thanks needs to go to Dr. Burge in adding in a few species of fish that the user missed to help improve the reliability of the data collected. This study was done by extensive roving around the large 100 m transect and some extended circling. Being a two tank dive and long range of mobility most of the reef area was observed LTS/M1 LTS/EBR DL/M1 DL/EBR M1/EBR 0.7397 0.6441 0.8293 0.6471 0.6452 46 40 48 46 42 62.18 62.10 57.88 71.09 65.1 and thus recorded for best results. Most of these studies were done as a dive buddy of someone else doing their research projects. In one case, the data collected was from observing the fish in the immediate area of the transect being used in another study. The laying of the transect may have possibly chased away some of the rarer species of fish and thus produced lower results. The more dives per location was useful in getting accurate results on what species live there. The best observed site using this method is Dancing Lady with six dives and the least accurate data by this idea is the East Back Reef. It was observed that doing just a general swim and see would yield moderate results. On the other hand, a study made up of actively searching could easily miss out on the fish that live in the open water above the reef. The best results were observed from doing a little of both observational methods. These studies were done at several locations that are both coral and algae driven systems. On the fore reef locations of Dancing Lady, M1 and LTS their was observed both a coral driven section and a algae section. The coral driven section was found from the reef crest to around 15 m depth. The algae zone was located below this point and extended to depths deeper then this study observed.

KORALLION The coral driven zone is commonly referred to as the Diadema zone or sea urchin zone that is heavily grazed to prevent algae from growing there. The higher species diversity was found in the coral driven systems. It was not looked at in this study, but it is possible to observe the micro ecosystems at a single dive site by comparing theses two ground coverings. When comparing Dairy Bull to the fore reef locations the differences are easy to observe because Dairy Bull is a coral driven system and most of the fore reef is algae driven. At the bottom of this paper are the seventeen common fish observed at all locations and the sixty eight species that were observed over this entire study. These were recorded only in their common name and not their scientific name as per time need to look them all up and record it. These fish are off of the reef.org check list to help aid in future studies at this site. Even with the many sources of error induced in this survey, the data collected is considered by the author to be reliable but may not necessarily be complete. The data collected should be as close to correct as possible with the fact that more then one survey was done at most of the locations. To obtain best results more studies would need to be done in a more in-depth, user-intensive approach to get a complete and accurate data collection of what species of fish are located at each location. ACKNOWLEDGMENT The author wishes to thank the staff of the Discovery Bay Marine Laboratory, University of the West Indies, for facilities support. Erin Cziraki, Scientific Dive Safety Officer, Coastal Carolina University and Erin J. Burge, Coastal Carolina University, contributed to the completion of this study. REFERENCES Alves de Guimaraens M, Corbett C, Combells C (1994) Species diversity and richness of reed building corals and macroalgae of reef communities in Discovery Bay, Jamaica. Acta Biologica Leopoldensia 16:41-50. Arias-Gonzalez, JE.,Legendre P, Rodriguez-Zaragoza FA (2008) Scaling up beta diversity and Caribbean coral reefs. Journal of Experimental Marine Biology and Ecology. 366: 28-36. Aronson RB. Precht WF (1995) Landscape pattern of reef coral diversity: A test of the intermediate distribution hypothesis. Journal of Experimental Marine Biology and Ecology. 192: 1-14. Bakus GJ, Nishiyama G, Hajdu E, Mehta H, Mohammad M, Pinheiro U, Sohn SA, Pham TK, Yasin Z, Shau-Hwai T, Karam A, Hanan E (2007) A comparison of some population density sampling techniques for biodiversity, conservation, and environmental impact studies. Biodivers Conserv 16: 2445-2455. Bellwood D, Hughes T (2001) Regional-scale assembly rules and biodiversity of coral reefs. Science 292: 1532. 62

Giovanni F, Ugland K.I,, Gray J S, Willis T J, Abbiati W (2008) Influence of rare species on beta diversity estimates in marine benthic assemblages. Journal of Experimental Marine Biology and Ecology. 366: 104-108. Pineda E, Halffter G (2003) Species diversity and habitat fragments: frogs in a tropical montane landscape in Mexico. Biological Conservation. 117: 499-508. Ricotta C (2008) Computing additive B-diversity from presence and absence scores: A critique and alternative parameters. Theoretical Population Biology. 73: 244-249. Thiere G, Milenkovski S, Lindgren P-E, Sahlen G, Berglund O, Weisner SEB (2009) Wetland creation in agricultural landscapes: Biodiversity benefits on local and regional scales. Biological Conservation. 142: 964-973. Zhuravlev AY, Naimark EB (2005) Alpha, beta or gamma: Numerical view on the Early Cambrian would. Palaeo. 220: 207-225.

Common Fish Species Blue tang French grunt Longfin damselfish Dusky damselfish Bicolor damselfish Yellowtail damselfish Blue chromis Graysby Harlequin bass Striped parrotfish Yellowhead wrasse Bluehead Clown wrasse Squirrelfish Longjaw squirrlefish Blackbar soldierfish Neon goby

17 Common Fish Acanthurus coeruleus Haemulon flavolineatum Stegastes diencaeus Stegastes adustas Stegastes partitus Microspathodon chrysurus Chromis multilineata Cephalophis cruentatus Serranus tigrinus Scarus iserti Halichoeres garnoti Thalassoma bifasciatum Halichoeres maculipinna Holocentrus adscensionis Neoniphon marianus Myripristis jacobus Elacatinur oceanops

All species recorded Fish Four-eyed butterflyfish Rock beauty Ocean surgeonfish Blue tang Bar jack French grunt Smallmouth grunt Bluestriped grunt Mahogany snapper

Reef fish biodiversity

69 Species recorded Chaetodon capistratus Holacanthus tricolor Acanthurus bahianus Acanthurus coeruleus Caranx ruber Haemulon flavolineatum Haemulon crysargyreum Haemulon sciurus Lutjanus mahogoni

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010. Yellowtail snapper Longfin damselfish Dusky damselfish Threespot damesfish Coca damselfish Beaugregory Bicolor damselfish Yellowtail damselfish Brown chromis Blue chromis Indgo hamlet Barred hamlet Butter hamlet Sergeant major Graysby Harlepuin bass Tobaccofish Great soapfish Fairy basslet Blue parrotfish Queen parrotfish Stoplight parrotfish Redtail parrotfish Princess parrotfish Striped parrotfish Redbrand parrotfish Yellowtail parrotfish Hogfish Creole wrasse Yellowhead wrasse Bluehead Slippery dick Clown wrasse Squirrelfish longspine squirrelfish Longjaw squirrlefish Blackbar soldierfish Glasseye snapper Neon goby Redlip blenny Yellowhead jawfish Spotted scorpionfish Sanddiver Trumpetfish Sharpnose puffer Balloonfish Porcupinefish Black durgon Orangespotted filefish Glassy sweeper Spotted goatfish Yellow goatfish Spotted drum Spotted moray

Ocyurus chrysurus Stegastes diencaeus Stegastes adustas Stegastes planifrons Stegastes variabilis Stegastes leucostictus Stegastes partitus Microspathodon chrysurus Chromis cyanea Chromis multilineata Hypoplectrus indigo Hypoplectrus puella Hypoplectrus unicolor Abudefduf saxatilis Cephalophis cruentatus Serranus tigrinus Serranus tabacarius Rypticus saponaceus Gamma loreto Scarus coeruleus Scarus vetula Sparisoma viride Sparisoma chrysopterum Scarus taeniopterus Scarus iserti Sparisoma aurofrenatum Sparisoma rubripinne Lachnolaimus maximus Clepticus parrae Halichoeres garnoti Thalassoma bifasciatum Halichoeres bivittatus Halichoeres maculipinna Holocentrus adscensionis Holocentrus rufus Neoniphon marianus Myripristis jacobus Heteropriacanthus cruentatus Elacatinur oceanops Ophioblennius macclurei Opistognathus aurifrons Scorpaena plumieri Synodus intermedius Aulostomus maculatus Canthigaster rostrata Diodon holocanthus Diodon hystrix Melichthys niger Aluterus schoepfii Pempheris schomburgki Pseudupeneus maculatus Mulloidichthys martinicus Equetus punctatus Gymnothorax moringa

Dusky squirrelfish Spotted trunkfish Checkered puffer Reef squirrelfish Redspotted hawkfish Remora

Sargocentron vexillarium Lactophrys bicaudalis Sphoeroides testudineus Sargocentron coruscum Amblycirrhitus pinos Remora remora

KORALLION

Reef fish biodiversity

Coastal Carolina University Studies in Coral Reef Ecology, Discovery Bay, Jamaica. 2010.

KORALLION

Reef fish biodiversity