SEAW ORDS TheMarineOption Program Newsletter
September 2021
Volume XXXVI, Number 8
Aloha, and welcome to the September issue of Seawords! Welcome back to school! We're so excited to be on campus again and are looking forward to a great fall semester full of ocean-themed fun. In this issue, learn about fish schools (pg. 4), read about the comb jelly (pg. 8), and discover new habitats on pages 12-17. W hat would you like to see more of in Seawords?Send in your thoughts, and follow us on Twitter and Instagram at @mopseawords!
Zada Boyce-Quentin, SeawordsEditor, & Matilda Phillips, Associate Editor
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Contents 2: LETTER FROM THE EDITOR 4: BACK TO SCHOOL 6: THE NEW FIFTH OCEAN 8: CREATURE OF THE MONTH 12: W ELCOME TO THE TW ILIGHT ZONE 14: THE PLASTISPHERE 18: INVASIVE ALIEN SPECIES 20: CHANGE IN DOMINANT REEF SPECIES AT PALMYRA ATOLL
Photo Credits Fr ont Page: Comb jelly. By: Orin Zebest, Flickr. Tabl e of Contents: Stingray. By: Ed Schipul, Flickr. Back Cover : Eel. By: Elias Levy, Flickr.
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School of fish. Photo by: David Lanham, Flickr.
BACK TO SCHOOL W ith the new school year beginning, we thought we'd highlight some animals whose school is never out of sessionfish! Fish aggregate primarily as a defense mechanism against predation, and in some cases to help them gather food more efficiently. W hen different species swim in large groups, it is referred to as a shoal, whereas a school refers to a tightly organized group of one species moving in a coordinated way. W hat's especially impressive about schools of fish is that they self-organize. Each member of the school coordinates perfectly with their neighbors to form the illusion of one cohesive movement. This is accomplished with the help of each fish's lateral line; an organ which detects subtle changes in water pressure that let the animal know what the other fish around it 4 | Seawords
are doing! Schooling has proven to be an effective method for evading predators. W hen pressed, schools of fish employ a number of complicated defense tactics, including the 'bait ball', wherein they form a large sphere with individuals hiding behind others in the school to expose fewer fish to a threat. Many species of fish form schools of truly massive sizes; for example, schools of herrings have been estimated to include up to four billion fish! However, herrings are not the only fish that school. In November of 2020, UH researchers discovered an aggregation of deep-sea eels on a seamount. Scalloped hammerhead sharks have also been known to school in order to catch prey. Welcome back to school, and remember to just keep swimming! SEPTEMBER 2021
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Ocean waves. Photo by: Richard Keeler, Flickr.
The New Fifth Ocean By: Brenna Loving, UH W indward CC MOP Student 6 | Seawords
You are probably familiar with the Pacific, Atlantic, Indian, and Arctic oceans, recognized by the world as the four major oceans of Earth. However, there is officially a new ocean to be added to the mix-- the Southern Ocean. Scientists have agreed for years that this body of water around Antarctica is different from any other ocean, but the official recognition internationally of the Southern Ocean as the fifth ocean in the world came on June 8th of this year?s W orld Oceans Day. W hat makes this ocean different from the rest?The Southern Ocean functions in an entirely different way than the other four oceans, and is geographically positioned differently as well. The other oceans are defined by the continents that surround them, whereas the Southern Ocean is defined by the continent of Antarctica, which it surrounds. The division between the Southern Ocean and all other oceans to which it is connected is determined by the Antarctic Circumpolar Current, or ACC. This current flows west to east around Antarctica and borders a difference in ocean water from the surrounding water. Inside the current, the water is colder and not as salty as the surrounding waters. Additionally, the current pulls in water from all of the world?s oceans, thus serving as a driving force for the ?conveyor belt?mechanism of all oceans for transporting heat to different parts of the world as cold water sinks towards Antarctica. This cold water serves an important role in the migratory patterns of various species of whales and seabirds. It is also a home to certain species of whales, penguins, sea birds, and seals that thrive uniquely in this environment. However, the effects of climate change have gradually increased the temperature in this ocean, and thus impacted the organisms that inhabit it. Those effects are still being monitored and studied by scientists. The distinction of the Southern Ocean internationally also serves as a conservation opportunity for the National Geographic Society and other organizations that wish to bring awareness to this body of water. W ith a separate classification and distinction, attention can be better directed towards this ocean and all of the factors that make it worth focusing on when discussing climate change and conservation. The unique structure and biodiversity of the Southern Ocean play a large role in the health of all of the world?s oceans, and consequently deserves extra attention and conservation when combating climate change.
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Comb jelly. Photo by: Jeff, Flickr.
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Creature of the Month: Comb Jelly By: Alexandrya Robinson, UHM MOP Student SEPTEMBER 2021
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If you take a dive into an estuary, you might be dipping into the same area as a comb jelly. Despite the word ?jelly?in their name, these organisms are not "jellyfih", but actually ctenophores. The comb jelly?s unique comb plates, which they use to move up and down in the water, refract light in the water column and create the iconic appearance of a glowing rainbow along the oval body of the organism. Some species also bioluminesce at night! There are over 100 species of comb jelly that inhabit the ocean, many of which have been extant for over 500 million years. Although species of comb jellies can be found in every ocean on Earth, non-native species can sometimes travel to other bodies of water and become invasive there. The adaptable nature of the comb jelly allows it to colonize multiple areas of the ocean. They are carnivores, feeding primarily on zooplankton and salps. Although sometimes phytoplankton can also be found in the digestive tract of comb jellies, but their presence is most likely due to the feeding style of the organism. Comb jellies take in food by pumping water into the opening at the bottom of their bell and catching prey with specialized cells that are adhesive, called colloblasts, coating the inner tentacles. Unlike the cnidarians (including true jellyfish) the tentacles of the comb jelly do not sting.
Comb jelly. Photo by: Kent McFarland, Flickr.
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Comb jelly. Photo by: Eva Funderburgh, Flickr.
W hen swimming, the comb jellies flare out two lobes to which the tentacles are attached in order to collect even more food until they are covered, at which point the lobes are taken into the body. Comb jellies are typically constant feeders, although in areas with poor nutrient availability, comb jellies can reduce their physical size to require less food, allowing them to survive in suboptimal environments- even in highly polluted waters. In these low nutrient environments, comb jellies have also been known to cannibalize their young. Full-grown comb jellies can ingest other juvenile and adult comb jellies. Mature comb jellies reproduce by releasing both male and female gametes during the summer months. According to the Chesapeake Bay Program, some species of comb jelly reach sexual maturity within two weeks, and a 2012 study published in Biology Lettersfound that one species, Mertensia ovum, was capable of reproducing while still in the larval stage. In some cases, low salinity does impact this sexual maturity. The hermaphroditic nature of the comb jellies allows even a single jelly to populate a whole new area on their own, which is another advantageous adaptation, and one that makes them especially insidious as an invasive species. Comb jellies are lots of fun to see, but be mindful! These ctenophores are incredibly delicate and can easily break apart if removed from the water. SEPTEMBER 2021
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W elcom Twiligh
By: Haley Chasin, U
The twilight zone, otherwise known as the mesopelagic zone, is located 200 m-1000 m (650-3,300 feet) below the sea.This zone is known for its high pressure, freezing temperatures, and low light. These unique environmental factors have caused organisms to develop special adaptations that enable them to survive in such harsh conditions. For instance, many have large eyes, are thin and small to help with camouflage, and have large teeth and jaws in order to capture more food. One example of these is the bristlemouth, which has an enormous gape size -- larger than its body -- which it uses to capture prey. It is the most abundant vertebrate on the planet; for every human there are an estimated 100,000 bristlemouths. Animals ranging from the smallest phytoplankton to some of the largest nekton on the planet can be found dwelling in the twilight zone. A not-uncommon adaptation here is bioluminescence, which is used for counter-illumination, to attract prey, and for mating displays. Counter-illumination is the use of light-producing organs to illuminate the ventral side of an organism in order to blend in with downwelling light.
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me to the ht Zone
UHM MOP Student
The mesopelagic zone is important because it helps regulate climate, storing 2-6 billion tons of carbon annually. It also supports a healthy ocean ecosystem, containing approximately ten times more fish than the rest of the ocean. The twilight zone also helps support food webs, by providing marine snow for species in the lower depths after species vertical migration. The largest migration on Earth is found between the mesopelagic zone to the epipelagic, or sunlight, zone. This migration, called the Diel Vertical Migration, might play a key role in pulling CO2 from the atmosphere. This process, in which animals move between the mesopelagic and epipelagic zones on a daily basis, enables animals to hide from predators in the deep while also getting food from the epipelagic zone. There is still lots to know about the mesopelagic zone, therefore more research needs to be done.New technologies are currently measuring the biomass of organisms and tracking individuals in the hopes of uncovering more information about this strange area of the ocean and the animals that live there!
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Microplastics. Photo by: Chesapeake Bay Program, Flickr.
The Plastisphere By: Brenna Loving, UH W indward CC MOP Student 14 | Seawords
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Microplastics. Photo by: Oregon State University, Flickr.
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The region of the ocean consisting of mass amounts of plastic, though not new in existence, has been identified as the ?plastisphere?by marine microbiologist Linda Amaral-Zettler through a 2010 plastic and biofilm study. This ecosystem classification began with including bacteria and fungi, but now includes larger organisms that live among and within the vast volume of drifting plastic. This unique, man-made ecosystem is home to many evolving microorganisms, and is proving to become a vital part of the ocean ecosystem as a whole. Recently, it has been discovered that there are species of microbes and bacteria in this ecosystem that have started to evolve in order to better consume and process plastic. In July of 2021, two bacteria were found to have the ability to break down polyethylene terephthalate, the most common material used to manufacture the seemingly endless amounts of plastic bottles that litter the oceans. These bacteria were identified as Thioclava sp. BHET1 and Bacillussp. BHET2. Additionally, Japanese scientists discovered a bacterial species named Ideonella sakaiensisthat is capable of consuming plastic due to a newly evolved enzyme. The presence of these bacteria is the result of the Zoebell effect, which describes how plastics become submerged in water and release carbon, iron, nitrogen, and phosphorus-- elements that attract and harbor bacteria, including those now capable of breaking down these plastics. Though the discovery of these bacteria is recent, it is likely that the evolutionary processes required to become capable of breaking down these materials began long before plastic materials infested the waters at the concentrations we know today. In regards to Earth?s evolutionary timeline, plastic has only been in existence for a short time, but its components have not. Thus it is reasonable to conclude that the bacteria we see today breaking down plastic has been evolving to consume the chemicals of plastic, like those found in oil for millions of years. The question now is how useful these plastic microbes could be in managing or decreasing the volume of plastic in marine ecosystems. W hile they could be a crucial part in combating plastic waste and its harmful effects, scientists are remaining reserved in their expectations of plastic eating bacteria. There is still much to be learned about the plastisphere and the organisms that inhabit this unique ecosystem.
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Invasive Alien Species By: Chloe Molou, UHH SeawordsLiaison For those living on the Big Island of Hawai?i, the sounds of the coqui frogs after dark are certainly not unfamiliar. Coquis are frogs native to Puerto Rico, and after being introduced to Hawai?i in the 1980s, have become a widespread invasive species with no natural predator to regulate their populations. Invasive alien species (IAS) are non-native organisms to an ecosystem and can cause physical, environmental, and economic harm to said ecosystem. IASare proving to be one of the major threats to biodiversity in both terrestrial and marine ecosystems, especially on islands. Humans are the primary spreaders of IAS, with a well-documented history of knowingly introducing non-native organisms to places in which they settle. Invasion science, as defined by Richardson and Ricciardi (2011), is the ?study of the causes and consequences of the introduction of organisms to the areas outside their native ranges?(p. 1461). This is a relatively new field of science, and of course, shows gaps in areas of study. As most research in this field would be carried out via observations, decades of data often need to be collected in order to quantify the impacts of IAS.
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Lionfish. Photo by: Mandy Jansen, Flickr.
Taxonomic bias is another issue currently being faced in IASstudies, specifically marine IAS, and has directly led to the lionfish becoming the ?poster child?of IAS. The lionfish first appeared in the Caribbean in the early 2000s, ravaging reefs throughout the region and has since become the subject of 40%of invasive marine fish studies. Hannah Watkins and Helen Yan discussed these figures in a paper published in Conservation Lettersin May of this year. Watkins and Yan had noticed disparities between research on IASin different ecosystems and found that marine IASto be understudied when compared to aquatic and terrestrial IAS. Only 39%of the 970 marine IAShave appeared in peer-reviewed studies, and less than 6%of marine IASwere the subject in studies quantifying their impact. Watkins and Yan (2021) also discussed the taxonomic bias present in marine IASresearch and how this issue is circular; species with known and measured impacts are normally favored for future studies, which leads to the neglect of understudied marine IASand the perpetuation of the ?poster child?species of IAS. Of the 970 marine IAS, 55%have been studied only once, and 8%have been studied more than 10 times. Chordates accounted for 38%of all marine IAS research, echinoderms accounted for less than 2%, with fish and Mollusca being the groups with the most species studied. For the best understanding of the impact IASare having, and will continue to have on native species, there must be more diversity in the taxa targeted for research. Identifying patterns in invasive taxa may help lead to the development of effective management strategies to ease the impact of IAS on native organisms.
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Palmyra Atoll. Photo by: USFWS Pacific Region, Flickr.
Change in Reef Species Ato
By: Georgia Jo UHM MO
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Dominant s at Palmyra oll
ohnson-King, OP Student
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Palmyra Atoll. Photo by: USFWS Pacific Region, Flickr.
A study conducted by marine biology researchers from the University of Hawai?i at M?noa which found that the biodiversity in the Palmyra reef is changing has been featured in Coral Reefs: Journal of theInternational Coral Reef Society. The study, conducted on the reefs at Palmyra Atoll, a National Wildlife Refuge, found that the reefs are shifting from being dominated by stony corals to corallimorphs. Corallimorphs are a kind of cnidarian commonly found in tropical waters and have been present on the reefs for decades; however, scientists from the School of Life Sciences and School of Ocean and Earth Science and Technology (SOEST) recently discovered an increase in their presence. ?There is concern among scientists and conservationists that the phase shift from stony coral-dominated habitats may be irreversible due to a negative feedback loop of coral decline and subsequent algal, sponge, or corallimorph domination,?said Kaitlyn Jacobs, lead author of the published study.
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Researchers used mitochondrial DNA to precisely point to the species of corallimorph that was most invasive. Taking samples from four different individuals, they found the invader is not a new species. Instead, the corallimorph responsible for the invasion is most closely related to a species from Okinawa, Japan. This shift in dominance is almost certain to have negative impacts on reef ecosystems, as corallimorphs are adaptable, fast competitors which can easily take over wide swathes of territory. ?In the last decade, Palmyra?s nearshore reefs have been invaded by corallimorph colonies that can rapidly monopolize the seafloor and reach 100%cover in some areas,?Jacobs said. It is incredibly important that we protect coral reefs. This problem is not unique; marine ecosystems around the world are seeing similar shifts due to climate change and pollution. These cases will only increase in severity unless we take global action.
Palmyra Atoll. Photo by: USFWS Pacific Region, Flickr.
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Vol u m e XXXVI, Nu m ber 8 Editor : Zada Boyce-Qu en tin Dr. Cyn th ia H u n ter (em in en ce gr ise) Jeffr ey Ku wabar a (em in en ce gr ise) W r itin g Team : Br en n a Lovin g, Ch l oe M ol ou , Caitl in Tsu ch iya, Al exan dr ya Robin son , H al ey Ch asin , an d An n am ar ie Coffar o Seawor ds- M ar in e Option Pr ogr am Un iver sity of H awai ?i , Col l ege of Natu r al Scien ces 2450 Cam pu s Road, Dean H al l 105A H on ol u l u , H I 96822-2219 Tel eph on e: (808) 956-8433 Em ail : <seawor ds@ h awaii.edu > W ebsite: <h ttp:/ / www.h awaii.edu / m op> Seawor ds is th e m on th l y n ewsl etter n ewsl etter of th e M ar in e Option Pr ogr am at th e Un iver sity of H awai?i. Opin ion s expr essed h er ein ar e n ot n ecessar il y th ose of th e M ar in e Option Pr ogr am or of th e Un iver sity of H awai?i. Su ggestion s an d su bm ission s ar e wel com e. Su bm ission s m ay in cl u de ar ticl es, ph otogr aph y,ar t wor k , or an yth in g th at m ay be of in ter est to th e m ar in e com m u n ity in H awai ?i. an d ar ou n d th e wor l d. All photos ar e taken by M OP unless other wise cr edited.