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 (cukerbenjamin@gmail.com)
Co-organizers:
Jeanette Davis, Hampton University (Jeanette.davis@hamptonu.edu)
Presentations
04:30 PM
Assessing Freshwater Influence on Water Column Stability, Nutrient Cycling, and Phytoplankton Productivity in the Canadian Arctic Archipelago (9385)
Primary Presenter: Frances Crable, University of Illinois at Chicago (fcrabl2@uic.edu)
The Canadian Arctic is vital for regulating climate and carbon uptake through ice and freshwater exports and high productivity rates. Changes in physical conditions and nutrient inputs related to freshwater distribution affect marine biota by altering nutrient availability and access(Carmack and McLaughlin 2001). These changes can impact phytoplankton function and productivity. It is known that freshwater is being supplied to the CAA, but the effects of its constituents on coastal ocean production have not been thoroughly studied in the CAA region. This study aims to use stable isotopes and continuous water quality data to assess how freshwater inputs influence water column stability, nutrients, and primary production, specifically focusing on phytoplankton photosynthesis, carbon uptake, and nutrient utilization. The presentation will cover biogeochemical cycling from Nome, Alaska, to Pond Inlet, Nunavut, examining how water properties and productivity vary across the CAA. This will involve single-turnover active fluorescence measurements of gross primary production, continuous water quality assessments, and macronutrient concentrations. Water-stable isotopes will help identify freshwater sources in the coastal Canadian Arctic, including river, glacial, and sea ice melt. Additionally, this presentation will discuss C, N, isotopic composition of suspended particulate organic matter (POM), allowing us to trace the sources and transformation processes of organic matter within the water column. Data collection occurred during a commercial cruise through the Alaskan Arctic and the CAA's Northwest Passage aboard the MS Roald Amundsen from August 23 to September 17, 2022. Our spatial and temporal observations will be extended by comparing them to available satellite measurements. This chemical and biological data provides us with an expansive dataset that gives spatial context to traditional depth profiles and a better understanding of the physical, biological, and chemical properties in this historically understudied region.
04:45 PM
Optimization of eDNA Methods for Detecting Cetaceans in Southern California (9407)
Primary Presenter: Yeishmary Soto Muñiz, University of Puerto Rico, Rio Piedras (yeishmary.soto@upr.edu)
Monitoring practices are essential for evaluating the status of cetacean populations and identifying threats posed by human activities. Environmental DNA (eDNA), which consists of genetic material released by organisms into their environment, offers an innovative assessment method. For this project, data was obtained from the California Cooperative Oceanic Fisheries Investigations (CalCOFI). This research aimed to detect cetaceans off the coast of Southern California and assess the effectiveness of eDNA as a complementary tool to established visual and acoustic monitoring methods. A total of 242 samples were extracted (n=242) and over 350 Polymerase Chain Reactions (PCR) were conducted, resulting in approximately 10% positive outcomes of cetacean DNA. Basic Local Alignment Search Tool (BLAST) sequencing results showed the putative presence of delphinids and whales. These results show eDNA as a promising applicable tool for studies that aim to conserve rare, cryptic, and elusive species. Future research directions include optimizing eDNA methodologies and incorporating the evaluation of abundant whale food sources to map potential habitats. Ongoing work will focus on determining the most effective methods for detecting rare targets, such as using marine mammal-specific vertebrate markers with amplicon sequencing or species-specific assays.
05:00 PM
CULTIVATING, CHARACTERIZING, AND IMAGING AMMONIA OXIDIZING ARCHAEA FROM DISTINCT NORTH AMERICAN COASTAL ECOSYSTEMS (9458)
Primary Presenter: Lauren Sells, Department of Biology and Marine Biology (las8247@uncw.edu)
Ammonia-oxidizing archaea (AOA) play a significant role in the nitrogen cycle by consuming ammonia and producing nitrite as the first step of nitrification. Despite their recent discovery and abundance globally, very few representatives of AOA have been cultivated from the environment. This project aims to prepare a variety of cultured and enriched taxa of AOA from within Class Nitrososphaeria for imaging and to observe any physiological differences between these groups. Using enriched AOA cultures in our laboratory maintained for the last 2-12 years, selected candidates were prepared for a growth experiment and fluorescence imaging. We will further characterize these AOA cultures by identifying morphological differences between taxa obtained across varied environmental features including salinity and temperature. The primary goal of this project focuses on imaging these archaea to determine their external features, ultrastructure, and surface layer (S-layer) via Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM). Our cultivated AOA that will be imaged and characterized include Nitrosarchaeum, Nitrosopumilus, and several unidentified subgroups. We hypothesize that our cultures will have distinct sizes, shapes, and exterior features (e.g., archaella), as previously cultivated soil and marine taxa appear distinct. Finally, we hope to define methodologies to characterize previously undefined ‘species’ of AOA from coastal marine ecosystems.
05:15 PM
Examining the effect of reef structural complexity on cryptobenthic fish assemblages (9464)
Primary Presenter: Kyra Jean Cipolla, University of Texas at Austin (kyrajean.cipolla@utexas.edu)
Coral reefs are one of the most diverse and valuable ecosystems on Earth. Rapid environmental change is shifting coral communities toward reefs dominated by stress-resistant, often less structurally complex species, which may influence the ability of reefs to support biodiversity and provide ecosystem services. However, detailed links between environmental conditions, three-dimensional structural complexity, and small reef-associated species are not fully resolved and may vary among regions. One group of reef fishes that are tightly associated with the benthos and occur in high densities are ‘cryptobenthic’ fishes, which are defined by small body size. Cryptobenthic fish are central to energy and nutrient fluxes that support reef fish biomass and, by virtue of their tight association with the benthos, perhaps highly responsive to changes in reef geometry. To test this, we examined the relationship between structural complexity, environmental conditions, and cryptobenthic fish community composition from Long Reef, Belize. Specifically, using underwater surveys and 3D-photogrammetry, we determined the rugosity, fractal dimension, and surface height of sites along the forereef and obtained fine-scale wave acceleration. Using enclosed clove oil stations, we collected cryptobenthic fish to quantify fish community composition. Our major overall finding was that structural complexity in the form of rugosity corresponds to the diversity of cryptobenthic reef fishes. Additionally, we showed that community composition may be driven by reef structure and environmental conditions. Our study demonstrates how fine scale structural complexity helps disentangle reef characteristics that make habitats suitable for small yet important reef fishes.
05:30 PM
MARINE AND TERRESTRIAL SEDIMENT ON ALGAL TURF LIMITS HERBIVORY PRESSURE AND SPECIES RICHNESS (9527)
Primary Presenter: Zuri Murph, Hampton University (zuri.murph@my.hamptonu.edu)
When disturbance leads to coral mortality, herbivorous fish provide strong top-down control that maintains turf algae in a short healthy state, favoring coral recruitment and recovery. While it is well known that marine sediment deters fish herbivory, the effect of terrestrial sediment, which is increasing on coral reefs due to climate change and coastal development, remains understudied. This study examines the effect of marine and terrestrial sediment on fish herbivory rate on algal turf. We compared three sites (n=10 plots per site) in Mo’orea, French Polynesia with different turf heights (LME, p<0.001) and sediment depths (p<0.0001). Total fish herbivory rates, quantified from video recordings of bite rates on replicate experimental plots, did not vary between sites (Kruskal-Wallis, p>0.05). Rather, bite rates for individual species as well as the species richness of the fish taking bites differed across sites. Richness and herbivory rates were highest where sediment and turf were lowest. Both herbivory and fish diversity declined at the site with marine sediment and long turf and were lowest by far at the site with terrestrial sediment and long turf. Overall, results showed that terrestrial sediment deterred herbivory more than marine sediment. Thus, increases in sedimentation, particularly of terrestrial sediments, associated with climate change could further degrade coral reefs by decreasing total herbivory and the species richness of the herbivore community, likely further inhibiting coral recovery.
05:45 PM
Unleashing the Green Menace: A Closed Mesocosm Study Assessing the Effects of an Invasive Green Crab (Carcinus maenas) on Eelgrass and Benthic Infauna (9618)
Primary Presenter: Kaitlin Macaranas, Western Washington University (macarak@wwu.edu)
Eelgrass estuaries are diverse coastal ecosystems severely threatened by the synergistic effects of climate change and invasive species. The invasive European green crab (EGC; C. maenas), a known ecosystem engineer and voracious omnivore, can devastate eelgrass beds and displace native species, with rising temperatures facilitating their northward spread along the North American coast. Despite this threat, the overall ecological impact of EGC on eelgrass and benthic infauna—key components of estuarine food webs—remains poorly understood in the Salish Sea. One of the largest eelgrass beds in North America, the Padilla Bay National Estuarine Research Reserve, is facing an early-stage C. maenas invasion, prompting concerns over continued sustainability and conservation. We conducted a short-term study to understand how EGC might alter eelgrass survival (Zostera marina and Z. japonica) and benthic communities in the bay. In an approved quarantine facility, replicate mesocosm tanks containing sediment and eelgrass transplanted from Padilla Bay were divided into two treatments: EGC and no EGC. After nine days, we assessed eelgrass loss and infaunal species diversity. Preliminary results indicate visible eelgrass loss with EGC exposure and higher average macroinvertebrate abundances in the control tanks. These results suggest trophic cascades may occur in response to EGC habitat disturbances and foraging. Understanding how EGC influences Padilla Bay is crucial for enhancing conservation and sustainability efforts within this vital estuary.
SS01C - ASLO Multicultural Program Student Symposium
Description
Time: 4:30 PM
Date: 27/3/2025
Room: W206A