Research opportunities are increasingly offered to undergraduate students in an effort to help them understand marine and aquatic sciences and to offer them an opportunity to consider this field as a career. Undergraduates who have conducted research are invited to present their results in this general session that will highlight the wide variety of student research and provide opportunity for interested faculty to discuss your project with you. The Research Experience for Undergraduate (REU) program brings large numbers of undergraduate students to marine institutions for summer research programs, and students who have participated in REU programs are particularly invited to submit to this session. Students are not limited to this session, and we encourage any undergraduate student who wishes to submit an abstract to a specialized science session in the subject of their research to consider that option as well.
Lead Organizer: David Fields, Bigelow Labs for Ocean Sciences (dfields@bigelow.org)
Co-organizers:
Lisa Rom, NSF (elrom@nsf.gov)
Presentations
06:30 PM
SPATIAL AND TEMPORAL PATTERNS OF ABUNDANCE OF GRASS SHRIMP (PALAEMONETES SPP.) IN THE MARYLAND COASTAL BAYS (4642)
Primary Presenter: Jocelyn Lucente, University of Maryland Eastern Shore (jl572@humboldt.edu)
Grass shrimp (Palaemonetes spp.) are among the most abundant macrocrustaceans in estuaries of the US Atlantic and the northern Gulf of Mexico. Although grass shrimp is a significant link in the food web of the Maryland Coastal Bays (MCBs), information is lacking on its population dynamics. The objectives of this study were to evaluate the temporal and spatial variation of grass shrimp abundance in the MCBs using data collected from 1994 to 2017. We hypothesized that grass shrimp abundance is higher in the northern bays than in the southern bays due to higher densities of macroalgae and phytoplankton in the northern bays. Results showed a higher catch-per-unit-effort (CPUE) of grass shrimp in the northern than southern bays for each month (p < 0.05) from April to October. Grass shrimp CPUE was highest in the spring and lowest in the summer months when the abundance of juvenile fishes is typically at its peak. The CPUE of the shrimp also varied among years, although no increasing or decreasing trend was observed. The lowest mean CPUE of the shrimp was noted in 1996 (40+1.05SE) and the highest occurred in 2002 (608+12SE). The temporal and spatial variations in CPUE of grass shrimp likely influence their trophic role as major prey for several fish species, predators of meiofauna and small infaunal invertebrates, and as grazers on epiphytic algae on saltmarsh grasses in MCBs.
06:30 PM
Settlement of Mustard Hill Coral (Porites astreoides) Larvae on Carbon-Efficient Alternative Concretes (5484)
Primary Presenter: Dalia Bercow, Haverford College (drbercow@gmail.com)
Scleractinian corals are slowly disappearing, disrupting the marine ecosystems that they build. Active restoration efforts aim to improve coral reef habitats and rebuild coral communities by out-planting young coral in highly-damaged areas. However, this process often relies on concrete bases made with Portland cement. The manufacturing of cement is a key contributor to global greenhouse gas emissions, so coral propagation presently contributes to the destruction of scleractinian reefs via global warming. We examined the larval settlement of a robust coral (Porites astreoides) on a variety of concrete alternatives designed to have lower greenhouse gas emissions than traditional concrete. The goal of our study was to identify a greenhouse gas-efficient concrete alternative that maximizes the settlement of P. astreoides larvae, and minimizes greenhouse gas emissions for potential use in reef restoration efforts. We experimentally examined and quantified the settlement and metamorphosis of P. astreoides larvae on seven concrete tile types. Although average larval recruitment differed among tile types, a Kruskal-Wallis ANOVA revealed that these differences were not significant (p=0.23). The variance between tiles of the same composition leads us to recommend at least 10 replicates in future experiments to ensure statistical power to differentiate between materials. Lower greenhouse gas alternative concretes were not significantly better or worse than ceramic tiles or traditional concrete for the settlement of P. astreoides larvae and thus could be suitable for coral settlement.
06:30 PM
COLLOIDAL TRACE METALS IN THE CENTRAL PACIFIC (5514)
Primary Presenter: Catherine Kaylor, Texas A&M University (catiekaylor@tamu.edu)
Trace metals (Fe, Zn, Cu, Co, Ni and Mn) act as essential micronutrients for phytoplankton, serving as the foundation of the marine food web. Not all trace elements act as micronutrients, with some metals (Pb and Cd) instead having toxic effects on the marine environment. Studying the distribution of trace metals throughout the global ocean is critical to estimating ecosystem health and understanding biogeochemical processes. Metals can be partitioned into three size classes: soluble, colloidal, and particulate. Dissolved metals (<0.2 um) consist of both soluble (“truly dissolved;” <0.003 um ~10 kDa) and colloidal phases (0.003 – 0.2 um). Colloids are tiny particles that are still small enough to pass through the 0.2 um dissolved filter membrane; they are considered an intermediary between soluble and particulate. The size partitioning of trace metals is important because it impacts the fate and lifetime of different elements, particularly their bioavailability. In this study, the concentration of colloidal trace metals in the central Pacific Ocean is compared to the colloidal composition of trace elements in the South Pacific, Atlantic, and Arctic Oceans. Seawater samples were collected on the US GEOTRACES GP15 Pacific Meridional Transect cruise conducted along the 152°W meridian of the central Pacific Ocean, from Alaska to Tahiti in Fall 2018. This cruise was the first basin-scale meridional trace element analysis in the Pacific Ocean covering, a wide range of biogeochemical features, allowing for the analysis of differences in inter-basin colloidal composition.
06:30 PM
THE IMPACT OF NEARSHORE RECREATIONAL ACTIVITIES ON ARSENIC EXPOSURE IN CONTAMINATED LAKES: A STUDY OF SEDIMENT DISTURBANCE AND WATER QUALITY (5526)
Primary Presenter: Kirsti Lipphardt, University of Washington Tacoma (klipphar@outlook.com)
Climate change is drawing more people to lakes to cool down, but contaminated sediments may reduce accessibility. Many lakes in Western Washington are contaminated with arsenic (As) due to a history of smelting. The sediments in these lakes contain higher concentrations of As than the water column. Prior work found As from shallow lakes is deposited into nearshore sediment, resulting in concentrations similar to deep lake sediments. We hypothesize the physical action of nearshore play may suspend As-contaminated sediments and increase As concentrations in the water column, consequently increasing As exposure through accidental ingestion of suspended sediments. Samples were collected from three lakes varying in As contamination levels. To analyze changes in As availability in the water column, we collected filtered and unfiltered water samples before and after simulated nearshore play. Surface sediment samples were analyzed for grain size and total As. We found a significant increase in As concentration after sediment disturbance in the unfiltered samples but no significant change in As concentration of filtered samples. The results suggest contaminated sediments increase the risk of As exposure during nearshore play due to the addition of As-contaminated suspended sediments. This study provides insight into the potential risks of recreational activities in As-contaminated lakes and highlights the importance of understanding the effects of sediment disturbance on water quality and human health.
06:30 PM
Oyster Farm Effects on Sediment Composition and Infauna (5932)
Primary Presenter: Simon L'Heveder, University of Edinburgh (simonlheveder27@gmail.com)
In the Cape Shore region of Delaware Bay, New Jersey, USA, about 2 km of intertidal oyster farms overlap spawning habitat for the Atlantic horseshoe crab (Limulus polyphemus) whose eggs provide food for several migratory shorebirds of conservation concern. Oyster farming can modify sediments through deposition of organic and inorganic byproducts. This may alter habitat for infauna, which are prey for the aforementioned animals. This study examined whether oyster farms in Delaware Bay alter organic and inorganic carbon content of sediments and infauna abundance. Surveys were conducted in two paired farm-control plots (90x60 m) across a 1 km stretch of tidal flats. In Spring 2021 and 2022, 156 sediment cores (218x20 mm) were collected to estimate infauna diversity and abundance. In July 2022, 80 duplicate sediment cores (16x20 mm) were collected to determine relative proportions of organic and inorganic carbon across each plot. The effect of farms on infauna abundance varied among taxa and years. Total abundance was significantly higher in the farms in 2022, suggesting a positive effect of oyster farms. Additionally, polychaete abundance was significantly greater in farm plots in both years. Results of a generalized linear mixed effects model indicated significantly higher inorganic carbon levels in farm sediment, but no difference in organic carbon. These results indicate that oyster farms can alter sediment composition and infauna abundance, but further research is needed to determine if there is a direct relationship between sediment composition and infauna.
06:30 PM
BEACH CHARACTERISTICS, HORSESHOE CRAB (LIMULUS POLYPHEMUS) EGGS, AND OYSTER FARMS (6229)
Primary Presenter: Catherine Carrion, Virginia Polytechnic Institute and State University (catherinec20@vt.edu)
The Delaware Bay supports the world’s largest spawning population of horseshoe crabs (HSC). The massive abundance of eggs deposited on the beach is a critical resource for many animals including migratory shorebirds, gulls, and fish. Adjacent intertidal oyster farming activities may influence HSC egg distribution, potentially impacting food availability for organisms foraging on the eggs. Beach characteristics may also influence HSC egg distribution, potentially confounding the effect of oyster farms. This research examined how several beach characteristics were associated with the distribution of HSC eggs, and if any associated beach characteristics confound potential associations between farms and egg distribution given the limited and fixed distribution of farms available for study. In Spring 2021 and 2022, HSC egg surveys were conducted in four paired farm-control plots (90 m x 180 m) across a 2 km stretch of beach in Delaware Bay. In 2022 six beach characteristics were examined in each plot: depth of anoxic layer, beach width, beach slope, sand grain size composition, percent cover of Spartina alterniflora, and adjacent land use. Correlation analyses indicated that beach characteristics were not significantly associated with the HSC egg distribution. Additionally, there was no consistent pattern between the beach characteristics and plot type (farm vs. control). These findings suggest that beach characteristics were not confounding factors for other studies addressing the relationship between oyster farms and HSC egg distribution at this site.
06:30 PM
SHEDDING LIGHT ON THE LARVAL “BLACK BOX”:DEVELOPING BIOMARKERS FOR THE LARVALSTAGES OFMYTILUS EDULIS (6230)
Primary Presenter: Aubrey Mitchell, Maine Maritime Academy (aubreymitchell1@icloud.com)
<em>Mytulus edulis </em>, commonly known as the blue mussel, is an important filter feeder in the Gulf of Maine, as well as a valued commercial fishery. Following fertilization, blue mussel larvae progress through several stages, including, trochophore, veliger, and pediveliger, a process which can last up to 35 days. During this time, the larvae remain in the water column. Tracking the microscopic larvae that drift with ocean currents and travel long distances is very difficult. Environmental RNA (RNA) from water samples has the potential to provide information on their life-history stage as gene expression profiles can differ significantly. In this study we identified and tested potential biomarkers for the larval stage of the blue mussel. The potential biomarkers were tested on blue mussel larvae and adult RNA as well as water samples. We have identified a potential marker that is specific to blue mussels with high expression levels in all larval stages. Blue mussels are economically and ecologically important. Developing molecular biomarkers is an important tool for assessing larval dispersal and connectivity which could enhance our understanding of conserving and managing this important fishery.
06:30 PM
Clumped isotope paleotemperature analysis of Campanian and Turonian foraminifera from southeast coastal Tanzania (7125)
Primary Presenter: Olivia Gadson, Georgetown University (omg12@georgetown.edu)
Remarkably well-preserved lower-middle Turonian (~92-93 Ma) and middle Campanian (~75-77 Ma) foraminifera samples from a Tanzania Drilling Project (TDP) drill site (~35°S paleolatitude) were analyzed for their carbonate clumped isotope (Δ47) composition to compare with previous oxygen isotope (δ18O) paleotemperature estimates and assumptions about the oxygen isotope composition of the regional seawater (δ18Osw). Reduced sample size requirements for Δ47 analyses using a cold finger configuration on a Nu Perspective dual inlet mass spectrometer (< 2 mg) enabled us to measure paleotemperature data for multi-species separates of benthic and planktic foraminifera from each stratigraphic interval sampled. Foraminiferal test wall preservation was documented using light microscope and SEM imaging of whole and dissected specimens. External appearance of nearly all Turonian and Campanian tests indicated good to excellent (glassy) preservation, but some infilling was observed following test dissections. Using a water flotation method to concentrate hollow, non-infilled tests, samples were pipetted into a sieve and dried for analysis. Preliminary Δ47 results are consistent with the expectation of cooler temperatures for benthics compared with co-occurring planktics and warmer Turonian surface and bottom water temperatures compared to the Campanian, with all Δ47 temperature data considerably warmer than at present day. A subset of samples exhibits very high Δ47 temperatures (>35°C) and considerably depleted d18O values, consistent with diagenetic alteration and infilling of some specimens. These results highlight that when shallowly buried and well-preserved specimens are available, Δ47 analyses of foraminifera can quantitatively resolve paleotemperature and δ18Ow values for geologic time intervals of greenhouse paleoclimate, such as the Late Cretaceous.
06:30 PM
BACTERIA AND ARCHAEAL COMPOSITION ON THE TEXAS COAST FOLLOWING HURRICANE HARVEY (7289)
Primary Presenter: Joelle Ann Roman, Texas A&M University (joelleannr@gmail.com)
Hurricane Harvey was a category four storm that lasted from 17 August - 02 September 2017 and brought unprecedented rainfall to Texas and Louisiana, resulting in 124 trillion liters of freshwater entering the Gulf of Mexico (GoM). With climate change predicted to increase storm severity, Hurricane Harvey may represent an increasingly common form of future storms that moves more slowly and results in higher rainfall. Therefore, it is important to understand the impacts of Hurricane Harvey on the ecology of the Gulf of Mexico to predict how future storms will impact coastal ecosystems. To understand how the microbial ecology of the GoM was affected by Hurricane Harvey, 142 seawater samples were collected from water column profiles along the Texas coast from Galveston to Baffin Bay as well as from Flower Garden Banks National Marine Sanctuary over two cruises during September 22 - October 1st, 2017. DNA was extracted from each sample before amplification of the V4 region of the 16S rRNA gene using Polymerase Chain Reactions. Patterns of community composition reveal stronger depth-associated differences between samples than temporal differences at the same depths. We will present results of compositional analysis as well as comparisons to post-Harvey microbial communities analyzed previously from Galveston Bay to determine if those community members were enriched downstream on the TX shelf following the storm, correlations to seawater chemistry, and correlations to previously published phytoplankton group profiles from the same samples.
06:30 PM
ITS ALIVE! : AUTOMATED GLIDER ADCP DATA PROCESSING (5067)
Primary Presenter: Nikitha Shivakumar, Georgia Institute of Technology (nikithaskr@gmail.com)
Numerous complex instruments have been integrated into autonomous underwater gliders over the past two decades to investigate the biological, chemical, and physical properties of the ocean. Current profilers have been integrated for more than a decade and provide novel insight that can enable more accurate calculations of underwater current velocity. Subsurface currents and their variations in speed have been categorized as a physical oceanographic essential ocean variable within the Global Ocean Observing System Ocean Observations Panel for Climate (https://www.goosocean.org/). The velocity calculations are critical for understanding the transport of heat, salt, passive tracers, and pollutants in global oceans. Additionally, surface currents are a major player in climate, as they are responsible for the transport of water and the regulation of global climate and equal distribution of solar radiation. Ultimately, underwater velocity calculations can allow for more detailed and accurate regional and global ocean numerical models of upper-ocean dynamics. However, due to the large sizes of data and limited measurement platforms, subsurface currents and their velocities are greatly under-sampled in real-time. This research project aims to develop a procedure that efficiently processes large data sets of information collected by autonomous underwater gliders while at sea, enabling data transfer to shore in near-realtime. This process involves implementing an algorithm onboard a Slocum glider through the installation of software on a Raspberry Pi 4, which was found to be the most efficient microprocessor. Ultimately, this project will provide detailed insight into subsurface current velocities and expand our global ocean observing capabilities.
06:30 PM
MONITORING THE ENVIRONMENTAL DNA (eDNA) OF SHARKS IN THE RED SEA AND ITS RELATIONSHIP TO THE MICROBIOME. (5953)
Primary Presenter: Lina El Sayed Aly, The American University in Cairo (linaelsayed@aucegypt.edu)
Marine ecosystems are being negatively affected worldwide by several threats, including but not limited to, overfishing, warming, pollutants including plastics, rising sea levels, and changes in pH levels. Another serious and growing threat to marine ecosystems is the worldwide decline in shark populations which disrupts marine biodiversity and the maintenance of healthy marine ecosystems. Limited studies have investigated the Red Sea shark population and recent studies have mainly investigated the shark population on the Saudi Arabian side of the Red Sea. Thus, there is an urgent need to research shark populations in the popular tourist destination of the Red Sea. Recent shark accidents in the Red Sea are also poorly understood due to the lack of research on sharks. Our study utilizes environmental DNA (eDNA) isolated along the Egyptian Red Sea coast, in the region of Marsa Alam, in an area known for sharks’ presence and an area known to be deficient in sharks. Water was collected, and filtered on a 0.1 μm filter, and DNA isolation was followed by the amplification of a 171-bp 12S ribosomal fragment of the mitochondrial genome. Sequencing of both the former, and 16S rRNA is currently being carried out. The DNA metabarcoding data will provide insight into the difference in the shark community between the two sites, and its potential relationship with the microbiome. This study, therefore, aims to preliminarily monitor shark populations utilizing this new emerging method in the Red Sea to provide more insight into shark populations.
SS002P Undergraduate Research in Marine and Aquatic Sciences
Description
Time: 6:30 PM
Date: 8/6/2023
Room: Mezzanine