Bio-diversification in the Courtenay Bay Tidal Marsh Evaluating the estuary of the Marsh Creek watershed, prior to Harbour Cleanup, Saint John, New Brunswick. Tim Vickers Graeme Stewart-Robertson
This project was made possible through grants provided by the New Brunswick Environmental Trust Fund, Environment Canada’s Atlantic Ecosystem Initiative, the New Brunswick Wildlife Trust Fund, and the New Brunswick Internal Services Agency Employment Development [S.E.E.D. Program]. Special mention must also be given to the Chemical technology program of the New Brunswick Community College (Saint John) for their generous use of laboratory space and apparatus, and their technical guidance.
Executive Summary
The Atlantic Coastal Action program (ACAP) Saint John envisions the urban Marsh Creek watershed in Saint John, New Brunswick as the foundation of a world-class example of sustainable development. Specifically, the Marsh Creek Restoration Initiative (MCRI) proposes that with the pending (2013) cessation of untreated wastewater deposition in Marsh Creek, that three enhancements could be incorporated to provide social, economic and environmental benefits to future generations. The objectives of this study were to expand our understanding of the environmental attributes of Courtenay Bay, the tidal marsh and estuary of the Marsh Creek watershed. Field studies were conducted to ascertain the occurrence of diadromous fishes and migratory birds within the watershed. This project found that despite a diversity and abundance of aquatic and brackish habitats, there were no anadromous fishes in Marsh Creek upstream of the tide gates on the Courtenay causeway, whereas American eels were found to be ubiquitous throughout all sub-drainages of the watershed. The report did not ascertain the reason for the lack of anadromous fishes; however, the occurrence of five flapper-style tide gates is considered a likely contributing factor. The watershed was found to have lower than expected numbers of migratory shorebirds, however the diversity of bird species (thirty-five) observed was worthy of note. There were no Species At Risk shorebirds observed, but Bald eagles (a confirmed Species At Risk) were observed. The Courtenay Bay forebay’s Provincially Significant Wetland was confirmed as breeding habitat for ducks and geese. Black and Mallard ducks were widespread throughout all areas with many overwintering in open water areas. While this project found that the area is currently not a likely significant contributor to the stocks migratory birds, the urban centric location coupled with the diversity in species composition could support eco-tourism in conjunction with the growing internationally-originating cruise ship industry.
Background The Marsh Creek watershed is a 4,000+ hectare feature located in the eastern quadrant of Saint John, New Brunswick, Canada that drains directly into the Bay of Fundy. The watershed, which served as a valuable natural asset for early settlers, became an internationally recognized environmental concern due in large part to its receipt of untreated municipal wastewater and the existence of heavy creosote contamination in the sediments of its lower reaches. Locally, the creek is also subject to extreme flooding which is related to commercial and residential developments in its floodplain (located below extreme high tide) and crustal subsidence. Saint John, New Brunswick, as one of the most rapidly changing urban environments in Atlantic Canada, is currently undertaking several once-in-a-lifetime alterations that have the potential to significantly improve the water quality of inland and nearshore environments. The most noteworthy of these alterations is the pending completion (~ December 2012) of the Saint John Harbour Cleanup project, which will see a cessation of centuries of raw sewage discharges into Marsh Creek, Courtenay Bay, the Saint John Harbour, and subsequently the Bay of Fundy. Harbour Cleanup, which has resulted from two decades of dedicated community engagement by ACAP Saint John, represents the single greatest opportunity in recent history to restore the recipient nearshore water quality, thereby improving the habitat needed to increase (and potentially even restore) the diversity of both flora and resident and transient fauna. As such, this project represents one of the last opportunities in Canadian history to measure and document changes in biodiversity following the cessation of the discharge of untreated municipal wastewater into nearshore environments. Specifically, the objectives of this project are to; 1) Acquire baseline (pre-wastewater treatment) water quality measurements within the estuarine and aquatic habitats of Marsh Creek and the Courtenay Bay Forebay, hereafter referred to as the “Courtenay Bay tidal marsh�. These data include the recipient waters as well as those immediately above the zone of influence. 2) Acquire baseline floral biodiversity measures for the estuarine and aquatic habitats of the Courtenay Bay tidal marsh. These data include the recipient waters as well as those immediately above the zone of influence. 3) Acquire baseline faunal biodiversity measures for the estuarine, aquatic and riparian habitats of the Courtenay Bay tidal marsh. These data include the recipient waters and those immediately above the zone of influence as well as the adjacent land areas. 4) Analyse, summarise and present the data in a format that will enable comparable data to be collected in subsequent years. Specifically, the changes to biodiversity will be most closely monitored in the two years following Harbour Cleanup (2013 and 2014) by comparing to baseline values obtained this year (2102).
Figure 1. Harbour Cleanup construction activity looms over the Forebay portion of Courtenay Bay during ACAP’s flora survey operations.
Methodology The ambitious scope of the Bio-diversification in the Courtenay Bay Tidal Marsh project required a meticulously managed and systematic allocation of project resources to effectively meet its objectives. Specifically, the project was divided into broad categories, of which the first (Knowledge Acquisition) were ‘stand-alone’ activities designed to bridge gaps in existing information and meet definitive engagement targets, respectively; while the third (Promotion and Awareness) provided broad reaching interaction with extra-regional urban watershed-oriented stakeholders. A. Knowledge Acquisition The project management team determined that definitive gaps existed in knowledge categories considered to be critical success factors for the evaluation of Courtenay Bay’s bio-diversity. These factors included the occurrence of diadromous fishes (Fish Communities), plants (Flora Communities) and, migratory birds (Bird Communities). The methodologies used to measure these parameters follows. 1. Fish Communities Three different techniques were used to ascertain the occurrence of diadromous fishes within the Marsh Creek watershed. a. Fyke Netting Two Fyke nets were deployed between April 20 and June 14, 2102 near the terminus of Marsh Creek. One net was placed in the main creek channel upstream of the tide gates on the Courtenay Causeway, with a corresponding net being placed in the channel on the marine side of the tide gates in Courtenay Bay (Figure 2). The nets were fished within a 24 hour soak to reduce the risk of mortalities. Fish were identified, measured for total length, with representative specimens photographed for confirmation of field
identification. Nets were thoroughly cleaned in an iodine based liquid disinfectant (Premise Disinfectant) after each use to prevent the transfer of water-borne diseases within or between watersheds (Figure 3). b. Electroseining Electrofishing activities were conducted using a battery-powered Smith-Root LR-24 electrofisher. The certified operators were Tim Vickers, Graeme Stewart-Robertson and Crystal Colpitts, all of ACAP Saint John. The settings used were varied depending on the substrate, water conductivity and the effect they were having on fish. In most cases, the built-in quick setup option was used and minor adjustments (typically to the voltage) were made as necessary. The 'on time' and settings were noted upon completion of each site. Dip nets were used to capture fish which were then transferred to a 5 gallon bucket of water until they could be measured and released back to their original environment as quickly as possible. Electrofishing was conducted in Marsh Creek on September 20, 2012 in three sites located between the Marco Polo Bridge and the 1 Mile train bridge.
Figure 2. ACAP Saint John staff deploy Fyke nets in Marsh Creek downstream (left) and upstream (right) of the tide gates located in the Courtenay Causeway in Saint John, NB.
Figure 3. ACAP Saint John staff use pressure washers to remove physical debris, dirt and the iodine based disinfectant from Fyke nets used in Marsh Creek, June 2012. Latex gloves, rubber gloves, chest waders and full rain were required equipment during field sampling and the subsequent disinfection due to the high risk of disease related to the deposition of untreated municipal wastewater (raw sewage) into Marsh Creek.
c. Beach Seining Beach seines were used in two locations within the Marsh Creek watershed. Ashburn Lake was sampled on July 4 & 31, and on August 22, 2012 using a 10m x 1.5m seine (Figure 3). Three substrate types were sampled (sandy, mixed organic & rock, and organic) and were in keeping with historical sample locations conducted in each of the past five years. Sampling was conducted as part of an ongoing youth education program, and as a presence/absence study conducted by ACAP Saint John. Fish parameters (i.e. length, abundance, etc.) were not collected so as to maintain the health of the fish; however, presence / absence data was recorded with respect to any previously undocumented species in this lake. Fish were also sampled in the lower reaches of Marsh Creek in a brackish area referred to as the Courtenay Forebay. A 6m x 1m seine was used to determine fish community composition. The sampling took place on September 13, 2012 adjacent to the causeway and included six hauls. Total counts were taken along with sub-samples of total lengths. Figure 3. Beach seining Ashburn Lake.
2. Bird Communities Two sources of information were used to assess the usage of the Marsh Creek watershed by migratory bird species. First, the most up-to-date (2012) surveys on bird life in the lower reaches of Marsh Creek were provided from long-time Marsh Creek stakeholder CBCL Ltd., which had commissioned expert birder Jim Wilson to conduct the surveys. The reports themselves are confidential, and as such, only the most relevant highlights are provided herein. The surveys were conducted during two distinct seasons in 2012. The first survey period incorporated both a high water sample period on the morning of June 25, and a low water period (to expose potential feeding on the mud flats) on the morning of July 5, 2012. The second survey incorporated the shorebird migration timing period between early August and early October, 2012. The second source of information involved ACAP staff conducted research and field observations for species not identified in the aforementioned CBCL survey. Digital imagery was taken whenever possible to confirm sightings. 3. Flora Communities The Study Area is located within the Fundy Coast Ecodistrict, where vegetation communities are strongly influenced by the unique coastal climate. Milder temperatures both in Summer and Winter, and frequent fog and overcast conditions bring about reduced growing season, soil temperature, and fire frequency, while promoting vegetation communities that are more boreal in nature. Floral surveys were conducted at predetermined sites within the Forebay of Courtenay Bay. These sites were chosen for their diversity of drainage patterns and proximity to either the Causeway [therefore the bay itself] or inlet streams. Plots were measured to a 2 m diameter (identified during pre-sampling consultation as more reliable to conduct than the originally planned plot sizing), at which point identification of all constituent species was conducted. Photos of all species, along with samples of those species of indeterminate origin were taken from each plot. 4. Reptilian and Amphibian Communities Visual surveys for reptiles and amphibians were be conducted bi-weekly throughout the sampling period. The location and species for each siting was to be reported, and GPS tagged digital images taken (where possible) of each specimen.
B. Water Quality Monitoring Field pH: To test the pH in the field a field pH meter (Fisher Scientific, Accumet AP Series, Handheld pH/mV/Ion Meter) was used. The meter was standardized, prior to testing, using pH buffers 4 and 7. The probe of the meter was then immersed in the creek and moved in a small circular motion. This was continued until the value stabilized on the pH meter and that value was then recorded. This same procedure was repeated at each sampling site. Dissolved Oxygen: Testing the Dissolved Oxygen (D.O.) was also done in the field using a field meter (EcoSense DO200, Field/Lab, Dissolved Oxygen and Temperature Instrument). To standardize this meter it was necessary to know the atmospheric pressure in mBars and the salinity concentration in ppt. The atmospheric pressure
could be retrieved from an internet website, such as theweathernetwork.com. It was necessary to measure the salinity at every sampling site with a salinity meter and then the D.O. meter was re-standardized at every site as well. The probe of the meter was then immersed in the creek and moved in a small circular motion until the reading stabilized. This reading was then recorded and the method was repeated at every site. Total Suspended Solids: A total suspended solid (TSS) refers to the measurement of the dry-weight of the particles trapped by a filter through the filtration process. The solids are a mixture of organic (algae or bacteria) and inorganic (clay or silt) components. These suspended solids affect the turbidity or cloudiness of a water source and the suspended particles will scatter light as it tries to pass through the water. Some sources of organic and inorganic components, which contribute to TSS and turbidity are eroding soil, microscopic organisms, industrial and municipal effluent, and suspended bottom sediment. From early spring to early fall there is an increase in turbidity and TSS due to spring runoff and then microscopic organisms and algae blooms. Due to the increase in turbidity and TSS, through the seasons the amount of sunlight that algae and other aquatic life can absorb will decrease significantly and particles will settle out. The settling particles may then damage the habitat of small animals living in the sediment as it blankets the bottom. Total suspended solids (TSS) were measured using the vacuum filtration method. A Glass Fibre Filter Disk (Whatman Grade 934-AH Circles 55mm) filter was weighed and then placed in the filter apparatus. A predetermined sample size was slowly poured into the filter, and then the apparatus was rinsed three times with distilled water to ensure that all of the sample was filtered and none was left on the walls of the apparatus. Once the filtration was complete the solids and the filter paper were allowed to dry until a constant mass was reached, which indicated all moisture was removed from the sample and filter. The weight difference was then calculated and the determination of TSS, in milligrams per litre, was calculated and recorded. Orthophosphates: Phosphorus and nitrogen are essential plant and animal nutrients; phosphate is the form of phosphorus used by aquatic plants. In aquatic ecosystems nitrogen is generally readily available; however, phosphate is most often the limiting reagent for growth. Therefore when abnormal amounts of phosphates are introduced to aquatic ecosystems, it can rapidly cause increases in the biological activity of certain organisms and disrupt the ecological balance of the waterway. Some sources of phosphates are agricultural runoff (fertilizer), biological waste (sewage, manure), and industrial waste. The phosphate concentration was determined using the ascorbic acid method. The process involved mixing 25ml of each sample and one drop of phenolphthalein indicator with 4ml of a previously mixed combined reagent. The combined reagent was composed of 50ml of 5N Sulphuric acid, 5ml of potassium Antimonyl Tartrate solution, 15ml Ammonium Molybdate solution, and 30ml of Abscorbic acid solution. After the mixing was completed the samples were left to sit for at least 10 minutes but no more than 30 and then placed in the spectrophotometer. The transmittance and absorbance was then measured using the spectrophotometer and was recorded. Fecal Coliform:
Fecal coliform originates from vegetation but largely in the intestinal tract of warm-blooded animals and humans. Increased levels of fecal coliform could indicate failure in water treatment, a break in the integrity of the distribution system, or possible contamination with pathogens. Tests for coliform are inexpensive, reliable and fast (1-day incubation). Observing the fecal coliform levels and fluctuations can provide an estimation of the relative amounts of contamination of pathogens within the water supply. Fecal coliform can enter water sources through direct waste from mammals and birds, from agricultural and storm runoff, and from human sewage. However, their presence may also be the result of plant material or pulp or paper mill effluent. Fecal coliform bacteria thrive in polluted deep water areas with low dissolved oxygen counts and with slow moving current. Since, fecal coliform is an indication of the presence of pathogens, any water source that contains fecal coliform has the potential for transmission of diseases. The standard for recreational water quality is 200 fecal coliform per 100mL of water (10% not >400) (Halifax Task Force, 1990). The membrane filter technique was used for the testing for fecal coliform bacteria. Agar (m-FC containing 1% Rosolic Acid) was prepared and placed into sterile Petri dishes. A Millipore (EZ Pak membrane; white, gridded, 0.45µm pore size, 47mm) filter was added to a Microanalysis Filter Holder and centered accurately on the support screen. A predetermined sample amount was slowly added to the apparatus and vacuum was applied. Once the filtration process was completed the membrane filter was removed from the apparatus and placed into a previously created sterile petri dish containing a medium of m-FC agar prepared with 1% solution of Rosolic acid. The petri dishes were then incubated, upside down, at 44.5°C (±0.2°C) for 24 hours.
After 24 hours the petri dishes were removed from the incubator. Only the blue colonies on the petri dishes were counted. Using the dilution ratio of the sample used for the specific petri dishes, the colony forming units (CFU) per 100mL, of water, were calculated and recorded. The accepted way of expressing fecal coliform level in water is in terms of the number of colony forming units per 100 millilitres of water (CFU/100ml). Lab pH: The pH level was also tested in the lab. This was done by standardizing the pH meter, with the 4 and 7 buffers, and then immersing the probe into a beaker of the sample. When a pH measurement stabilized it was recorded and the probe was then rinsed thoroughly with distilled water, before repeating the procedure for the following samples.
Sites Five sampling stations, approximately 500m apart, were selected within the last 2km of Marsh Creek, including two in the on the Courtenay Fore bay (Figure 5). These sites were separated as equally as possible and were the locations that all samples and field testing took place.
Figure 5: Map of Sampling Sites
Site 1: (GPS Co-ordinates: 45.277506, -66.047122) Site one was located by the flood gates that separate Marsh Creek from the Courtenay Bay. By walking down to site two and then walking along the creek's edge it was possible to reach site one and attain the samples. Site 2: (GPS Co-ordinates: 45.281560, -66.048694) Site two was located approximately 500m upstream from the first site. It was possible to attain samples from this site by driving down to the very end of Hanover Street and the walking to the side of the creek. This site was located just prior to where Duchman’s Creek enters Marsh Creek, Duchman’s Creek had a much higher concentration of raw sewage than Marsh Creek.
Site 3: (GPS Co-ordinates: 45.284844, -66.052393) Site three (Figure 6) was again about another 500m upstream from its preceding site. To get to this area it is necessary to drive to the Sunbury parking lot and then walk to the side of Marsh Creek from there. This location was approximately two meters upstream of a raw sewage dump (including the St. Joseph’s hospital, anytime a toilet is flushed it is released directly to this location).
Figure 6: Sampling Site 3
Site 4: (GPS Co-ordinates: 45.288143, -66.048764) Site four, located another 500m up Marsh Creek was just past yet another raw sewage dump. To get to this area it was necessary to drive up the road that went past the Sunbury parking lot and out towards the trains, where you could park on the shoulder of the road and then walk to the side of the creek.
Site 5: (GPS Co-ordinates: 45.290998, -66.043606) Site five (Figure 7), the final sampling site, was located at the end of the portion of Marsh Creek that was being monitored and upstream of the raw sewage dumps. It was approximately 1.98 Km from the initial sampling site and located underneath the train bridge by Rothesay Avenue. To get to this location ACAP staff drove up Rothesay Avenue until the train bridge was met and then walked down off the shoulder of the road, underneath the bridge, to the side of the creek.
Figure 7: Sampling Site 5
C. Promotion & Awareness ACAP leveraged its diverse contact base and strong social marketing regiment to engage stakeholders and similar sustainability advocates outside of the geographic region of Saint John. Outreach included participation in international watershed forums, on-line discussions with extra-regional entities, social marketing (Facebook, LinkedIn, GooglePlus, Twitter and our website) and directed organisational engagement. Results Faunal Survey 1. Fish Communities a. Fyke Nets A total of 300 fish comprised of 12 different species were collected from 10 separate hauls between April 20 and June 14, 2012 (Table 2). The fyke net catch in the upstream (above tide gate) site contained eight species and was dominated by Mummichog (71.4%) followed by American eel (11.4%) (Table 2; Figure 8). The other six species comprised less than 5% of the total catch, with White suckers, Yellow perch and Threespine sticklebacks each at 4.3%, and Rainbow smelt, Pumpkinseed sunfish and Tomcod each at 1.4%. The downstream (below gates) site contained seven fish species, and the catch was dominated by Tomcod at 93.0%. Rainbow smelt comprised the second most-frequently captured fish (5%), with American eel, Brown trout, Winter flounder, White Perch and Atlantic herring each representing less than 1% of the remaining total catch (Table 2; Figure 9). White suckers were the largest bodied fish captured in either location. The one rainbow smelt captured above the tide gates had a substantially smaller body size (approximately one-half has long) than those captured in the marine environment (Figure 10).
Table 2. Summary of species, counts and total lengths (mm) of fish captured in Fyke nets from two sample stations located within the lower brackish region of Marsh Creek between April 20 and June 14, 2012.
Species Tom Cod Mummichog American Eel2 Rainbow Smelt
N 1 50 8 1
Above Tide Gates Ave Min Max Length Length Length % (mm) (mm) (mm) 1.4 112 1 79.9 79.9 70 96 11.4 338 290 440 1.4 73 -
N 214 1 11
Below Tide Gates Ave Min Max Length Length Length % (mm) (mm) (mm) 93.0 160.6 107 280 <1 450 5.0 181.2 140 208
White Sucker Three-spine stickleback3 Yellow Perch Pumpkinseed Sunfish Brown Trout Winter Flounder Atlantic Herring White Perch
3 3
4.3 4.3
293.3 57
218 47
382 67
-
-
-
-
-
3 1
4.3 1.4
121 101
107 -
141 -
-
-
-
-
-
-
-
-
-
-
1 1 1 1
<1 <1 <1 <1
125 97 116 125
-
-
1. Only 31 Mummichog were used in the calculation of average length 2. Only 5 eels used in calculations. Lengths are approximations as eels were not anesthetised. 3. Only 2 used in calculations
Figure 8. Photos of Mummichog and Yellow perch (top), White sucker (middle) and American eel (bottom) captured by Fyke nets in the Courtenay Forebay of Marsh Creek, 2012. Ruler demarcations are in centimetres (cm).
Figure 9. Photos of Tomcod (top), Rainbow smelt (middle) and Brown trout (bottom) captured by Fyke nets in Courtenay Bay, 2012. Ruler demarcations are in centimetres (cm).
Figure 10. A photo of a 73mm (TL) Rainbow smelt captured by Fyke netting in the Courtenay Forebay of Marsh Creek on April 20, 2012.
b. Electroseining A total of 144 fish comprised of six different species were collected from Marsh Creek using electrofishing on September 20, 2012 (Table 3). Electrofishers opted to only sample Sites 3, 4 & 5 (Figure 11) as Sites 1 & 2 had salinity levels (a.k.a. high conductivity) that made electrofishing unfeasible. Mummichogs were abundant in all three sites, comprising 30.7%, 35.1% and 72.0% of the total catch for Sites 3, 4 & 5, respectively (Table 3). Four-spine sticklebacks were the only other species found at each of the three locations, although their relative abundance was substantially lower at Site 5 (4.0%), versus 46.8% and 54.4% for Sites 3 and 4, respectively. One other species of note, the American Eel, was found in abundance at Site 3 (22.6%), with a considerable number being observed during electrofishing but unable to be captured. White suckers, Nine-spine sticklebacks and Pumpkinseed sunfish comprised less than 10% of the total catch in any single sample site.
Table 3. Summary of species, counts and total lengths (mm) of fish captured by electrofishing three sites in Marsh Creek, September 20, 2012.
Species White Sucker
n
Site 3 Ave length Range % (mm) (mm)
-
-
Mummichog American Eel Four-spine Stickleback Nine-spine Stickleback Pumpkinseed Sunfish Total
n
Site 4 Ave length Range % (mm) (mm) 627.0 76.5 100 35.1 40.5 27-84
n
Site 5 Ave length % (mm)
Range (mm)
2
8.0
54.5
54-55
18 72.0
39.8
22-49 103340
-
-
4
19 30.7
40.5
20
14 22.6
146.6
32-50 120260
-
-
-
-
3
12.0
241
29 46.8
271
22-35
31
54.4
24.6
12-36
1
4.0
32
-
-
-
-
-
1
1.8
30
-
1
4.0
27
-
-
-
-
-
1
1.8
27
-
-
-
-
-
62
57
25
1. Only twenty fish were sampled for lengths
Figure 11. Permanent sample sites used in Marsh Creek for fish collection and water quality analyses. c. Beach Seine Beach seining was used to collect fish from Ashburn Lake, on three different occasions (July 4 & 31, and August 22, 2012). Fish were neither measured nor counted due to warmer water temperatures, and the intent of this sampling was to serve as an educational medium for youth and as an annual presence / absence monitoring protocol for ACAP. Fish collected in 2012 included American eel, White sucker, Brown trout,
Pearl dace, Northern Redbelly dace, Blacknose dace, and Creek chub and for the first time in our records Mummichog. Six seine hauls were conducted in the Courtenay Forebay on September 13, 2012. The hauls netted a total of 658 fish, of which 656 (99.7%) were Mummichog, and the remaining two (0.03%) were Four-spine sticklebacks. Sixty-seven of Mummichog were measured and found to range from 20 to 81mm in total length, with an average length of 36.9 mm. The Four-spine stickleback ranged from 29 to 34 mm total length, with an average length of 31.5mm. 2. Bird Communities Twenty-five species were observed during the early summer survey, none of which were considered to be extraordinary in terms of their status or prior records. Five species of migratory shorebirds were identified during the autumn migration period, none of which were Species At Risk. In order of greatest to least relative abundance these were Semipalmated Sandpiper, Black-bellied Plover, Semipalmated Plover, Whimbrel and Greater Yellowlegs. Bald eagles (a Species At Risk) were also identified, and had been previously recorded by ACAP Saint John staff. A total of thirty-three different species of birds were observed during these two survey periods. The CBCL commissioned study noted that the mud flats and other habitats of Marsh Creek were not being frequented by numbers of migratory shorebirds to the extent that other areas in New Brunswick were. It is possible that invertebrate food sources in the Marsh Creek habitats are less than in other areas; however, this is speculative. ACAP staff also determined the use of lake habitat (especially Ashburn Lake) for nesting by loons, and the use of the Forebay for feeding by a White egret, as well as Blue heron (Figure 12). Wetland habitats in both the headwaters (Renforth Bog) and the tidal marsh in the Courtenay Forebay at the outlet of Marsh Creek were also used by Canada geese for nesting. Other migratory waterfowl, especially Black and Mallard ducks were widespread throughput all sub drainages of Marsh Creek, with many overwintering in the watershed.
Figure 12. Photo showing White egret (center) and Blue heron (lower right) feeding in the Courtenay Forebay of Marsh Creek. Photo courtesy of Graeme Stewart-Robertson.
3. Flora Survey
Figure 9: Flora Survey Plots
Table 4: Flora Survey Results Pl ot Genus species 1 Alnus incana Tussilago farfara Vicia spp. Solidago spp. [multiple] Fragaria virginiana Poa spp. [multiple] Juncus spp. [multiple] Trifolium spp. [multiple] Symphyotric hum novi-belgii Cicuta Equisetum Sonchus Potentilla
maculata palustre spp. spp.
Common Name Speckled Alder Coltsfoot Goldenrod Strawberry Grasses Rushes Clover Aster/New York Aster Spotted water hemlock, spotted parsley, spotted cowbane, suicide root Horsetail or Humpback Sow thistle Potentilla or cinquefoil
Other
Hieracium
spp.
Hawkweed
Glebionis Chrysanthem um
segetum
Corn Marigold
spp.
Chrysanthemum
Ranunculus
spp. spp. [sub-genus Sorbus] angustifolium spp. japonica palustre belladonna spp. spp. spp. spp. americana officinale
Buttercup
2 Sorbus Epilobium Rhamnus Fallopia Epilobium Atropa Leontodon Senecio Cirsium Rosa Sorbus Taraxacum Cladonia Plantago Parthenociss us Onopordum Arctium
spp. [multiple] spp.
Mountain Ash or rowan Fireweed Buckthorn/Alderleaf Buckthorn Japanese knotweed marsh willowherb Deadly Nightshade Hawkbit Ragworts or groundsels Thistle Wild Rose Mountain Ash Common dandelion Cup Lichen, British/Red Soldier Lichen, Reindeer Lichen Plantain
quinquefolia acanthium minus
Virginia creeper Cotton thistle, scotch thistle Lesser Burdock
Carex Rubus Lamiaceae Pastinaca Daucus Angelica Cornus Ulmus Artemisia Spiraea
spp. [multiple] idaeus spp. spp. carota spp. spp. americana spp. spp.
Sedges Raspberry
Anthriscus
spp. spp. [sub-genus Oxycoccus] spp. americana
Chervil, Parsley
3
Parsnip Wild carrot Angelica Dogwood American Elm Spirea, sometimes Meadowsweet
4 Vaccinium Sambucus Fraxinus
Cranberry elderberry White Ash
formerly Chrysanthemum segetum
Viola Valeriana Primula
spp. officinalis spp.
pansy or violet Valerian
Malus Alnus Centaurea Lactuca Populus Salix Salix Viburnum Mimulus Rubus Typha
domestica serrulata spp. spp. tremuloides spp. [multiple] nigra trilobum spp. hispidus latifolia
Apple tree Hazel Alder Thistle Lettuce Poplar, aspen Willow Black Willow Highbush Cranberry Monkey-flowers, Musk-flowers Swamp Dewberry, Swamp blackberry Cattail
Prunus Ribes Malus Verbena Alchemilla Sedum Chaenorrhin um Aster Prunus Oenothera Betula Betula Onoclea Thalictrum Polygonaceae [family]
spp. spp. spp. spp. filicaulis spp.
Cherry Gooseberry Crabapple Vervain Lady's mantle/Thinstem Lady's mantle Sedum, stonecrop
minus spp. nigra spp. papyrifera alleghaniensis sensibilis spp.
Dwarf Snapdragon Aster Canada Plum, Black Plum Evening primrose White birch Yellow birch Sensitive fern, Bead fern meadow-rue
spp.
knotweed
5
6
4. Reptilian and Amphibian Communities Purely visual reptile and amphibian surveys revealed no results of significance during sampling. The documentation of reptiles, but even more so amphibians would have been especially important as these animals have not been witnessed in great numbers in this degraded ecosystem during previous field excursions, these results are however consistent with past field seasons.
B. Water Quality Because Marsh Creek is brackish water and the area tested is so close to the bay, almost every test done could have been influenced by the direction of tide. Therefore, it was attempted to keep track of the tide while sampling and doing the field testing. However, because the samples are taken from an uncontrolled environment there are many other factors, aside from the tide, that may have had an effect on the results also. An example is amount of sewage being dumped into the water at the time of sampling; the amount could vary depending on the time of day. This variance was avoided as much as possible by collecting samples around the same time each day samples were taken. All data was recorded throughout the testing period and then reproduced in an electronic version afterwards, making any relations or trends easier to see. (Table 5)
Table 5: Example of electronic Data Table (pH) Date: Aug. 1st
Site 1
Sample 1 Sample 2 Sample 3
Temp. When Tested 18.8 18.8 18.8
pH 6.83 6.84 6.90
Site 2
Sample 1
18.8
6.87
Site 3
Sample 1
18.8
6.94
Site 4
Sample 1
18.8
7.13
Site 5
Sample 1
18.8
7.10
*** F Table nega a fina are n pesu resul mois pape origio weig
Results Continued:
Week 1: The data for every test was recorded on separate data tables and saved electronically. After that, all of the results were put into a summery table including the results for every test completed that week (Table 6). The pH measured in the field was slightly lower than when it was measured in the lab. This was most likely due to temperature change as the samples were stored in the refrigerator so they would have been cooler when measured in the lab than when they were in the field. As a rule pH goes up as the temperature goes down. The pH, for the most part, was an acceptable level, as most aquatic life prefer the pH to be between 6.5-8.0. The amount of total fecal coliforms, however, was not at an acceptable level. There were more fecal coliforms in these samples than there ever should be in water that is accessible by the public. While testing during week 1 the sample was not diluted at all and therefore the only site that had few enough colonies to count was Site 5. Zero fecal coliforms is the goal to have in any water that can be reached or used by humans. Of course, there will always be some because the creek is not in a controlled environment so there will always be wildlife that live near the creek, and agriculture runoff, and other natural things that can be handled. However, having greater than 1320 CFU/mL above stream of any raw sewage dumps indicates that the amount of fecal coliforms in Marsh Creek is unacceptable and unhealthy. The total suspended solids test had some errors, after calculating final masses some turned out to be negative or zero. This indicates that the filter paper might have had some moisture in it during its initial weighing. Although this error took place some data was still able to be retrieved. This test is a fair representation of the solids that float through Marsh Creek, however, it should be kept in mind that larger solids cannot be included in this test, and there were a large amount of large solids in Marsh Creek.
Table 6: Summary Table for Week 1
Results Continued: Week 2: During this week of sampling construction began at Site 4 which prohibited sampling and field testing for the rest of the testing period. The pH was inside the preferred range (Table 7) of most aquatic life, which is a great result. Again, the pH fluctuated a bit between the field and the lab which demonstrates the pH rising as the temperature of the sample lowers. The D.O at 20 ยบC in saltwater should be approximately 7.0 ppm and in fresh water approximately 9.1 ppm. This means that because Marsh Creek is brackish water the D.O is considerably low. Fish survive on dissolved oxygen, it is how they breathe, this means if the Dissolved Oxygen does not rise or continues to lower, Marsh Creek may inhabit fewer and fewer fish. Organic waste which can involve many things, sewage being one of the worst, is decomposed by bacteria. These bacteria then remove D.O from the water as they breathe. This is why it can be assumed that the raw sewage being dumped into Marsh Creek is a factor in the low D.O. levels recorded. Again in week 2 the total fecal coliform count was too high, the samples were diluted to 2ml of sample diluted to 20 ml with distilled water before filtering, this made it possible to get a count for Site 3 as well as Site 5. There were some large clusters of colonies, which made it impossible to count every single one, therefore the count recorded has ">" in front of it. This represents that there were "at least" the amount of coliforms recorded. The TSS were able to be recorded for at least one sample from every site this week, Site 2 showing that it had the most. This is most likely due to the tide as it was just beginning to go out, therefore all the sewage from upstream was just running into Site 2 on its way to the bay, but had not yet made it to Site 1.
Table 7: Summary Table for Week 2
Results Continued:
Week 3: This week involved the pH and D.O demonstrating the same results as the previous weeks (Table 8). When testing the fecal coliforms this week only 0.2ml of the sample was diluted to 20 ml before filtering. Even though these samples were diluted more than the previous weeks, it was only possible to count the colonies from Site 5. This is most likely due to the fact that the samples were taken just after high tide which would have allowed the water to come through the flood gates and fill the creek. As a result, all of the sewage would have been pushed upstream causing Sites 1 to 4 to be too populated to count and causing Site 5 to have the highest count it had during the entire testing period. It is assumed that the filter papers used in the TSS testing this week all held moisture as all that had a final weight above zero still resulted in very small masses.
Table 8: Summary Table for Week 3
Results Continued:
Week 4: The pH meter malfunctioned during the final week of testing, leaving it impossible to measure the pH in the field. However, because the pH measured in the lab this week, is similar to the results from previous weeks, it would be acceptable to assume that the field pH would also be showing a similar trend. The TSS results for this week were about an average fore the entire testing period. An interesting result was found, however, while testing for fecal coliforms (Table 5). This time the samples were diluted to 10-3 which meant there was very little sample filtered. This resulted in it being possible to count, fairly accurately, every site's colonies. Site 1 and all of Site 5's agar plates did not grow any colonies, however, Site 2 and 3's did (again there were a few large clusters of colonies present). The trend of fecal coliforms is assumed to be due to the tide. While sampling it was about mid tide, but on its way back in. This would cause a lot of water from the bay to be entering site one, which pushed all of the sewage entering Marsh Creek from Dutchmenâ&#x20AC;&#x2122;s Creek, which has a very high concentration of sewage, and from all of the raw sewage outfalls up into Site 2 and 3 but not yet reaching Site 5.
Table 5: Summary Table for Week 4
Salinity: The salinity was tested at all five sites on five separate days. The tide greatly affected these results, therefore it was arranged that the salinity was tested at all five sites, four separate times per day between low and high tide. This meant that in one day the sites would be tested from site one to site five every two hours. It was discovered after a couple days of testing that it took approximately an hour after high tide, in the bay, for the water to come through the flood gates and the creek to reach its "high tide". This also took place when the bay reached low tide. It took about an hour for the creek to drain out of the flood gates so that the creek could reach "low tide". The testing was then conducted to match the creekâ&#x20AC;&#x2122;s "high and low tide". The data was recorded in the field and then copied to an electronic form and put into tables. This made it very easy to calculate averages and also made the relations to the tide more noticeable. The average salinity for each site was then plotted on the following chart to demonstrate the relation with the tide (Graph 1).
Graph 1: Salinity measured at each site at different times where the creek’s "high tide" is at the earliest point on the graph and the creeks "low tide" is at the latest point in the graph.
Salinity 25
Salinity (ppt)
20
15 Site 1
Site 2 Site 3
10
Site 4 Site 5 5
0 7:12
9:36
12:00
14:24
16:48
Time
C .Promotion & Awareness Internet based interest in the Marsh Creek Restoration Initiative [MCRI] continued to grow through 2012, highlighting the value of this contemporary medium for knowledge dissemination. ACAP expanded the sphere of stakeholder engagement in the MCRI to include the Gulf of Maine Council on the Marine Environment, as well as the RBC Bluewater program. The MCRI was also promoted to a number of new stakeholders at the 2012 Living Waters Rally in Ottawa Canada. Two noteworthy participants included the New Brunswick Law Society who researched and presented a legal opinion on the liability associated with the creosote contamination in Marsh Creek at their 2012 Annual General Meeting, and he appointment of long-time ACAP advocate Larry Hildebrandt to the position of Professor and Chair in Marine Environment Protection at the World Maritime University in Malmo, Sweden.
Discussion A. Knowledge Acquisition 1. Fish Communities Fish collection activities in 2012 provided a wealth of new information and bridged many of the pre-existing gaps in our knowledge on the current use of this watershed by fish. The most valuable new information was acquired from the first Fyke netting procedures conducted above and below the Courtenay tide gates. This sampling was intended to not only provide information on species composition in these two locations, but also to determine if anadromous fishes were reaching the tide gates (assumed to be attempting to access Marsh Creek) and if anadromous fishes had successfully navigated the tide gates to enter Marsh Creek. The Fyke net results demonstrated definitive differences in fish species composition between the immediately above and immediately below tide gate locations, with the above gate population being representative of a more aquatic (freshwater) community, and the below gate community being comprised more of brackish and marine species. The results also demonstrated that species composition in the Forebay (upstream site) became less diverse as the water temperatures increased and water levels declined. The higher diversity may have been related to the downstream movement of fish associated with the spring freshet which would have also created a less brackish environment suitable for the white suckers, yellow perch and pumpkinseed sunfish captured earlier in the sampling period. Most notable was the lack anadromous fishes captured in the above tide gate location. The eleven large bodied Rainbow smelt captured on the marine side of the tide in the spring sampling suggests that this species may be attracted to Marsh Creek for spawning purposes. The lack of similar large bodied smelt captured in the upstream sampling location may be indicative of the barrier-effect being imposed by the flapper-style tide gates located on the Courtenay causeway (Figure 13). While there was one Rainbow smelt captured in the upstream sampling location, the relatively small size of this single specimen (half the length of those caught in the marine environment) suggests it may have originated from one of the lakes within the watershed and moved downstream during the spring freshet. It is also worth noting that historical records indicate alewives did frequent the Courtenay Forebay; however, no alewives were captured at either Fyke net sampling location despite the fact that hundreds of thousands of Alewives do pass by the mouth of Courtenay Bay via the St. John Harbour in their migration up the St. John River. As such, the lack of Alewives in the 2012 sampling provides no definitive answers to the question on the potential value of Marsh Creek as Alewife habitat as there may have been no historical use of this watershed by this species, or the construction of the causeway and tide gates (~ 1969) may have resulted in the extirpation of this species form the watershed. Additionally, any lack of subsequent spawning , and juvenile imprinting that may have occurred as a result of the tide gates posing a barrier to the upstream passage of anadromous fish, may have (over a period of the ~ 15 year maximal lifespan of Alewives) eradicated any living individuals with the imprinted migratory tendency to return to Marsh Creek. That is, without any living adult alewives that would have imprinted on Marsh Creek as juveniles, coupled with the gregarious schooling nature of this species, there may be few (no) remaining alewives that would be inclined travel near the tide gates due to the chemical attraction from the Marsh Creek watershed.
Figure 13. Photo showing the five flapper-style tide gates located at the outlet of Marsh Creek during low tide conditions. The gate infrastructure is showing increasing signs of wear and erosion as indicated by the loss of concrete and the exposed rebar in the forefront of this image. The second most telling data acquired from fish collection activities related to the numbers of juvenile American eels collected in Site 3, just above the Marco Polo Bridge. The soft organic and fine sediments in this portion of the creek supported various patches of submerged aquatic plants, with the majority of these sparse patches hosting juvenile eels. ACAP Saint John has captured eels in all of the sub-drainages of Marsh Creek except the Fisher Lake drainage, although there are numerous anecdotal reports by anglers and swimmers that eels also occur there. These data suggest that the vast number of tributaries, lakes and interconnected wetlands within the Marsh Creek watershed have value as American eel habitat. The brackish Courtenay Forebay itself may also be providing substantial eel habitat; however, the higher salinity (and associated conductivity) thwarted any electrofishing determinations. It should be noted that the potential barrier to anadromous fishes posed by the Courtenay tide gates does not apply to the catadromous American eels. Juvenile American eels are notorious for their ability to navigate barriers (including waterfalls) and the numerous gaps and holes in the increasingly decrepit (Figure 10) tide gates would offer little resistance to the upstream migration of glass or pigmented elver eels. Beach seining was conducted to acquire additional data on fish community assemblages, especially on smaller bodied species or juveniles of anadromous fishes. There were no anadromous fish captured by beach seining, adding further credence to the suggestion that Marsh Creek is currently not providing spawning or rearing habitat for anadromous fish despite its scale and diversity of suitable habitats. The seining did indicate that the brackish waters of the Forebay were dominated (during the warmer and lower water periods of the late summer) by the hardy Mummichogs, with a smaller proportion of four-spine sticklebacks. The lack of other fish species in the pooled sections of the Forebay may reflect the brackish
conditions, or the poor water quality associated with the high concentration of untreated municipal wastewater, or a combination of both. This yearâ&#x20AC;&#x2122;s beach seining resulted in the first records of Mummichog occurring in Ashburn Lake. Given the distance of Ashburn Lake from brackish water, and the substantial vertical drops and fast flowing sections within its outlet (Ashburn Creek), suspicions are raised concerning how these fish have come to inhabit the lake. It is possible that beach seining in the previous five years failed to capture or recognise the species, or that they were introduced deliberately or inadvertently through anglers bait buckets. Regardless, their occurrence will be closely monitored in years to come. 2. Bird Communities Marsh Creek possesses a diverse array of avian habitats ranging from coastal mud flats, to remote lakes, to tidal pools to slow moving riverine sections. The transition from a slow moving shallow creek to brackish tidal marsh to coastal mud flats in the latter 2 km of the watershed is a likely factor in the diverse array of bird species identified in this section. While the numbers of migratory shorebirds witnessed appears less than other locales, the diversity of species has been reported as a contributing factor in the Forebay being considered one of the top bird watching locations in the province. While the total combined usage of habitats may not amount to Marsh Creek being considered a significant contributor to the numbers of internationally migratory bird species, the close proximity of this section to the urban core, its relative ease of access and diversity of species present suggest that it possesses good potential to support eco-tourism based activities such as bird-watching. This type of economic expansion in Saint John could be conducted in concert with the existing and growing cruise ship industry which currently brings tens of thousands of international visitors to the city each year.
B. Water Quality The objective of this project was to retrieve and record as much data as possible prior to the ceasing of the raw sewage outfalls. This was done by collecting samples and testing the water in six different tests for four weeks. The six different tests included testing pH and Dissolved Oxygen in the field as well as testing for total fecal coliform count, pH, Orthophosphates and Total Suspended Solids in the lab. The pH results appear to be at an acceptable level every week. There is an extremely unhealthy amount of fecal coliforms in Marsh Creek as well as a lot of Total Suspended Solids. The dissolved oxygen levels are low which is not good. Dissolved oxygen levels are depleted by the bacteria that form from the fecal matter being dumped into the creek. Fish survive by breathing dissolved oxygen which means, if the dissolved oxygen levels continue to lower fish will no longer be able to survive in Marsh Creek. C. Promotion & Awareness The broad reaching interest in the Marsh Creek Restoration Initiative appears to be founded on its diverse array of social, economic and environmental community benefits. This sustainability theme has now become more than just another buzzword, and appears to have rooted itself in contemporary culture. Of particular interest to those interacting with ACAP staff is the merits of using the urban Marsh Creek watershed as â&#x20AC;&#x2DC;soft infrastructureâ&#x20AC;&#x2122; which can be managed and expanded to provide resilience in the face of increasingly severe precipitation events. The knowledge exchange that has occurred on this topic re-affirms that the City of Saint John is not unique in the challenges it faces with respect to historical development pressures and
morphological changes competing against new viewpoints and perspectives on the value of embracing and enhancing urban natural capital.
Closing The Marsh Creek watershed possesses the natural attributes capable of providing spawning, nursery and rearing habitats for anadromous fishes; however no such fish were found to be utilising these resources. While the reason for the lack of anadromous fish in Marsh Creek has not been substantiated, it is reasonable to suspect that the tide gates located at its terminus on Courtenay Bay are posing a barrier to their entry into the watershed. Increasing fish passage into Marsh Creek could add considerable value to the overall environmental integrity of his ecosystem, and provide increased environmental and social (recreational angling) benefits to the community. The existing bird life already provides ample natural capital from which to build an eco-tourism industry to complement the existing and growing cruise ship industry in Saint John.
References CBCL Ltd. 2012 Shorebirds Surveys â&#x20AC;&#x201C; Courtenay Bay, Saint John, NB. 2012. Unpublished. CBCL Ltd. Bird Survey â&#x20AC;&#x201C; Courtenay Bay, Saint John, NB. 2012. Unpublished.