This session is for undergraduate and beginning graduate students, primarily affiliated with the ASLO Multicultural Program (ASLOMP). Students will present their research findings in a friendly atmosphere that encourages constructive criticism. Appropriate submission from students not affiliated with ASLOMP will also be considered. Students may present in this session only once. They are encouraged to present subsequent work in regular sessions.
Lead Organizer: Benjamin Cuker, Hampton University (benjamin.cuker@hamptonu.edu)
Co-organizers:
Tiara Moore, Black in Marine Science (ceo@bims.org)
Deidre Gibson, Hampton University (Deidre.gibson@hamptonu.edu)
Presentations
10:30 AM
TRAIT BASED ECOLOGY FOR MARINE MACROALGAE PROVES A POWERFUL APPROACH FOR QUANTIFYING ANTHROPOGENIC STRESSORS ON ALGAL-DOMINATED TROPICAL REEFS (4659)
Primary Presenter: Alyssa Fritz, University of Missouri (arfzkg@umsystem.edu)
Anthropogenic stressors on coral reefs (e.g. sedimentation, nutrient enrichment, overfishing) are driving ecosystem shifts from coral to macroalgal dominance. Managing these stressors requires quantification of magnitude and effect, which can be time consuming and costly. Trait-based ecology approaches in terrestrial systems have demonstrated how environmental conditions can shape plant community traits; we posit community traits can be leveraged as indicators of anthropogenic stressors in coral reef systems. To test this, we compared algal community traits across sites with varying nutrient, sediment, and overfishing stress on five fringing reefs on Moorea, French Polynesia. We quantified the relative strength of these stressors with bioassays, showed significant differences among sites, and identified stressor ‘hot spots’. We randomly collected 20-25 algae from each site, measured seven functional traits, and used an ordination approach to delineate trait space, quantify occupancy across sites, and link both occupancy and trait values to environmental drivers. We found sites varied significantly in their occupancy of trait space, and loading plots indicated trait values shifted in response to environmental stressors. For example, algae responded to sediments by maximizing surface area relative to dry weight or height relative to dry weight, both traits likely aiding in acquisition of light. These results demonstrate algal community traits provide insights into the intensity of anthropogenic stressors, providing crucial information to guide local monitoring plans.
10:45 AM
RAMICRUSTA, AN INVASIVE ENCRUSTING ALGAE CAUSES MORTALITY IN CARIBBEAN CORAL LARVAE (4671)
Primary Presenter: Kayla Cayemitte, Woods Hole Oceanographic Institution and Ursinus College (Kayla.cayemitte2157@gmail.com)
Coral reefs are vital ecosystems that provide a habitat to marine life while protecting our coastlines from storms and creating job opportunities for local communities. The settlement of planktonic coral larvae plays an essential role in the growth and longevity of coral reefs. Settlement occurs when coral larvae attach to a substrate and metamorphize into a juvenile coral, adding to an existing reef or beginning a new coral reef. It is known that coral larvae tend to settle and metamorphize on crustose coralline algae which produces beneficial chemical cues that promote settlement. <em>Ramicrusta textilis</em> is an encrusting alga that is highly invasive in the Caribbean. In addition to its rapid spread, there is no record of juvenile coral recruitment on <em>R. textilis</em> which has raised concerns about its suitability as a substrate for settlement. In this study, we examined the effects of <em>R. textilis</em> on <em>Porites astreoides</em> and <em>Favia fragum</em> coral larvae settlement, including mortality and substrate interaction (attachment or settlement of larvae onto a substrate). Our results indicate that there is a significant increase in larvae mortality and a decrease in substrate interaction in both species when introduced to <em>R. textilis</em>. This study suggests that <em>R. textilis</em> may limit coral settlement on Caribbean reefs.
11:00 AM
SPECIES DISTRIBUTION MODELING OF CLIMATE-VULNERABLE WEST COAST GROUNDFISHES (4696)
Primary Presenter: Janelle Layton, Oregon State University (janelle.layton@oregonstate.edu)
Anthropogenic climate change is causing major changes in the world’s oceans, affecting the distribution and productivity of marine species of economic and cultural value. In the U.S., federal fisheries managers are engaged in research efforts to further our understanding of the vulnerability of managed fish stocks to climate-driven changes. Contributing to this effort, this study used species distribution modelling combined with downscaled ocean climate projections to project future distributions of 32 species of U.S. West Coast groundfishes. The best-fitting model was chosen for each species based on the combination of bottom temperature, DO, and substrate variables that best predicted withheld data using 2-fold cross-validation. Biomass distributions were then projected for each species in each year from 1980 to 2100. We observed a wide range of future distribution patterns among study species including movement north, movement offshore, an overall decline in CPUE, an overall increase in CPUE, movement deeper in the water column, movement shallower in the water column, a combination of various outcomes, and minimal change in CPUE. Overall, there are many potential consequences of distribution changes for groundfishes along the west coast in response to climate change. Potential outcomes depend on the life history and climate vulnerability status of each species, where generally species with highly sensitive life history patterns and/or are ranked to be the most climate vulnerable show the most concerning distribution patterns.
11:15 AM
Microplastic-Associated Chemicals Negatively Impact Coral Fertilization Success (6137)
Primary Presenter: Keiko Wilkins, University of Hawaii at Manoa (keikow2@hawaii.edu)
Microplastic pollution presents an emerging stressor of concern to coral reef ecosystems. The physical impact of corals ingesting microplastics has been well studied, but the chemical threat that microplastics may pose to these organisms has been understudied. The effect that microplastic-associated chemicals may have on coral reef health and reproduction has been unexplored. Therefore, the goal of this study was to determine if a difference exists between the effects of microplastics themselves and their associated chemicals on Montipora capitata fertilization rates. For this, gametes were exposed to either 4 types of 5 mm microplastic spheres (nylon, polypropylene, high-density polyethylene, or low-density polyethylene) at one of three concentrations (50, 100 or 200 particles per/L) or leachates from these same microplastics. The results showed that gamete fertilization was not impacted by plastic particles themselves, but leachates from these plastic particles heavily reduced fertilization rates for Montipora capitata. These findings are the first to show that microplastic-associated chemicals are an important stressor affecting coral reproduction. Thus, microplastic pollution might pose a threat to coral replenishment and persistence on coral reef ecosystems.
11:30 AM
Oyster Pathogen Monitoring Using Third Generation Portable Sequencers (5068)
Primary Presenter: Matthew Franolich, Molloy University (mfranolich1@lions.molloy.edu)
Crassostrea virginica, the eastern oyster, is considered a keystone species in New York waters and throughout the US east coast, and understanding challenges to eastern oyster restoration is a top priority of conservation groups. Like other marine species, the eastern oyster hosts a complex microbiome, including beneficial bacteria, opportunistic commensals, such as Aeromonas media, and potentially lethal pathogens such as Roseovarius crassostreae, Haplosporidium costale, and Vibrio splendidus. Detecting bacterial oyster pathogens is a challenge because of their broad diversity and because pathogens are often closely related to nonpathogenic strains. In this project, we developed a detection method using portable third generation sequencers that can capture, with high-resolution, the genetic diversity of members of the wild oyster microbiome, including potential pathogens. Oysters were collected from various restored reefs in the Hudson River Estuary system, preserved, and genomic DNA extraction was optimized for efficiency and for preservation of long strands. Full-length rRNA genes (4,200 bp) were amplified and sequenced on a Nanopore MinION system, giving high-resolution taxonomic coverage that allowed for the identification of several pathogens from these microbiomes and identification of infected individual oysters. As the project expands, we will apply this method to determine how environmental factors such as warming can impact the proliferation of pathogens at restored reefs, and try to determine thresholds for the onset of bacterial infections.
11:45 AM
Quantification of meltwater features on Greenland and Antarctic glaciers (4735)
Primary Presenter: Jordan McDavid, University of Tampa (jordan.mcdavid@spartans.ut.edu)
Glaciers are the largest freshwater reservoir on Earth, storing 68% of all freshwater on continents. They are a vulnerable component of the cryosphere, losing mass through calving events and melting (either at the surface or at the glacial bed). Glacial melting comprised of 21% of sea level rise over the last two decades. Large-scale calving events are well-documented and a focus of glaciological research. On the contrary, a relatively small amount is known about processes by which ice melts, is stored, and changes on the surfaces of glaciers. This study aims to categorize the different melt features, such as crevasses, ponds, streams, and blue ice, for Greenland and Antarctic glaciers, and determine their size and abundance. QGIS, an open-source geographic information system application, was used to map and measure the area and length of these features on Helheim Glacier on Greenland and Beardmore, Marsh/Nimrod, and Lennox King Glaciers on Antarctica. The results of this study showed that water-filled crevasses were the largest melt features present on all glaciers, averaging a size of 39.24 km2. Most of the other meltwater features were located within or near crevasse fields. The most abundant meltwater features overall were ponds with a total of 75 identified across all 4 glaciers, Marsh/Nimrod Glacier contributing 61 of those ponds. The least abundant as well as the smallest melt features were streams, with an average length of 28.49 km. On Helheim Glacier specifically, blue ice was the most abundant melt feature. This is important to our overall understanding of glacier mass loss and hydrology because it shows that the surfaces of glaciers are dynamic and store meltwater in a variety of features. These features need to be monitored and measured annually to understand their temporal variability and how/if surface meltwater contributes to sea level rise.
SS001B ASLO Multicultural Program Student Symposium
Description
Time: 10:30 AM
Date: 8/6/2023
Room: Sala Ibiza B