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Estimated Consumer Sensory Shell Life Of Fresh Blue Catfish Filets Stored In Ice (Ictalurus Furcatus), Robert A. Fisher

Reports

Blue Catfish (Ictalurus furcatus) is the largest species of catfish in North America where it is native to the Mississippi, Missouri, and Ohio river drainages. It was introduced in fresh water Virginia tributaries of the Chesapeake Bay to enhance recreational fisheries in the 1970’s, from which significant recreational and commercial wild caught catfish fisheries developed. Since introduction, Blue catfish populations have expanded from upriver freshwater habitat to brackish-water sub-estuaries with reports of blue catfish in the Chesapeake Bay proper. Blue catfish are voracious, opportunistic predators feeding on a variety of natural prey items, including native fish and shellfish species, and …

Virginia Seafood Sustainability, Samantha E. Askin, Robert A. Fisher

Reports

Virginia’s commercial fisheries operate sustainability under a suite of management tools based upon information received from marine scientists and fishery managers who regularly conduct biological sampling of fish while tracking commercial landings and other gathering of required information. Analyses of fishing effort and overall stock conditions, as well as formulas designed to calculate threshold limits for maintaining sustainable stocks are regularly performed. Restrictions on seasons, size, days at sea, and gear are imposed as needed to achieve management supporting long-term biological sustainability.

Intertidal Zonation Of Hemichordates In Soft Sediments, Kharis R. Schrage, Juselyn D. Tupik, Jonathan D. Allen

Arts & Sciences Articles

Intertidal zonation of organisms is well studied on rocky shores but less so in soft sediment communities. On rocky shores, communities are two dimensional, with biotic factors such as competition and predation setting the lower bound of a zone, whereas abiotic factors such as desiccation set the upper bound. In soft sediment communities, these patterns persist, but with a dynamic three-dimensional ecosystem occupied by mobile infaunal organisms, zonation can be more difficult to quantify and detect. Hemichordate worms, however, deposit fecal casts at the surface, which can be easily identified and counted, making them a potential model system for identifying …

Estuarine Microbiomes And Biogeochemistry: Impacts Of Spatiotemporal Variation, Algal Blooms, And Microplastics, Samantha Grace Fortin

Dissertations, Theses, and Masters Projects

Estuaries are biogeochemical hotspots connecting terrestrial and coastal ecosystems. Anthropogenic disturbances, including increased nitrogen loading and plastic pollution, may have significant impacts on estuarine carbon and nitrogen cycling by altering microbiome structure and functions. The overarching goal of this dissertation was to examine how microbiomes and their associated biogeochemical processes are influenced by natural variation and anthropogenic disturbances in the York River Estuary (YRE). In chapter 2, spatial and temporal variation in benthic microbiomes and the rates of denitrification, anaerobic ammonium oxidation (anammox), and dissimilatory nitrate reduction to ammonium (DNRA) were examined to determine biotic and abiotic drivers of nitrogen …

A Rapid Phenotype Change In The Pathogen Perkinsus Marinus Was Associated With A Historically Significant Marine Disease Emergence In The Eastern Oyster, Ryan Carnegie, Susan E. Ford, Rita K. Crockett, Peter R. Kingsley-Smith, Lydia M. Bienlien, Lucia S.L. Safi, Laura A. Whitefleet-Smith, Eugene M. Burreson

VIMS Articles

The protozoan parasite Perkinsus marinus, which causes dermo disease in Crassostrea virginica, is one of the most ecologically important and economically destructive marine pathogens. The rapid and persistent intensification of dermo in the USA in the 1980s has long been enigmatic. Attributed originally to the effects of multi-year drought, climatic factors fail to fully explain the geographic extent of dermo’s intensification or the persistence of its intensified activity. Here we show that emergence of a unique, hypervirulent P. marinus phenotype was associated with the increase in prevalence and intensity of this disease and associated mortality. Retrospective histopathology of …

A Decade Of Incorporating Social Sciences In The Integrated Marine Biosphere Research Project (Imber): Much Done, Much To Do?, Ingrid Van Putten, Rachel Kelly, (...), Kevin Weng, Et Al

VIMS Articles

Successful management and mitigation of marine challenges depends on cooperation and knowledge sharing which often occurs across culturally diverse geographic regions. Global ocean science collaboration is therefore essential for developing global solutions. Building effective global research networks that can enable collaboration also need to ensure inter- and transdisciplinary research approaches to tackle complex marine socio-ecological challenges. To understand the contribution of interdisciplinary global research networks to solving these complex challenges, we use the Integrated Marine Biosphere Research (IMBeR) project as a case study. We investigated the diversity and characteristics of 1,827 scientists from 11 global regions who were attendees at …

Modeling Changes In Baleen Whale Seasonal Abundance, Timing Of Migration, And Environmental Variables To Explain The Sudden Rise In Entanglements In California, Kaytlin Ingman, Ellen Hines, Piero L. F. Mazzini, Et Al

VIMS Articles

We document changes in the number of sightings and timing of humpback (Megaptera novaeangliae), blue (Balaenoptera musculus), and gray (Eschrichtius robustus) whale migratory phases in the vicinity of the Farallon Islands, California. We hypothesized that changes in the timing of migration off central California were driven by local oceanography, regional upwelling, and basin-scale climate conditions. Using 24 years of daily whale counts collected from Southeast Farallon Island, we developed negative binomial regression models to evaluate trends in local whale sightings over time. We then used linear models to assess trends in the timing of …

Ecological Monitoring Program At Vims Esl : Annual Report 2020, Paige G. Ross, Richard A. Snyder

Reports

An Ecological Monitoring Program (EMP) has been established at the Virginia Institute of Marine Science Eastern Shore Laboratory (VIMS ESL) for the coastal environment near the Wachapreague lab. The goals of the initiative are to 1) provide status and trends information to scientists who study and regulators who manage Virginia’s marine resources, 2) provide a scientific context for short-term research and grant proposals 3) provide pedagogical enrichment to educators for their classes, and 4) build capacity in staff expertise and training of interns and students at VIMS ESL.

The program formalizes and standardizes data collection for a long-term status and …

Variation In Seagrass-Associated Macroinvertebrate Communities Along The Gulf Coast Of Peninsular Florida: An Exploration Of Patterns And Ecological Consequences, Savanna C. Barry, A. Challen Hyman, Charles A. Jacoby, Laura K. Reynolds, Mark Kowalewski, Thomas K. Frazer

VIMS Articles

Seagrasses form vast meadows of structurally complex habitat that support faunal communities with greater numbers of species and individuals than nearby unstructured habitats. The Gulf coast of peninsular Florida represents a natural laboratory ideally suited to the study of processes that shape seagrass-associated invertebrate and fish communities within meadows of a single species of seagrass, Thalassia testudinum. This suitability arises from a pronounced structural and chemical gradient that exists over ecologically relevant spatial and temporal scales, as revealed by extensive monitoring of water quality and seagrass. We hypothesized that seagrass-associated invertebrate communities would vary across five estuarine systems spread …

Ribbed Mussel Geukensia Demissa Population Response To Living Shoreline Design And Ecosystem Development, Donna M. Bilkovic, Robert Isdell, Amanda G. Guthrie, Molly Mitchell, Randolph M. Chambers

VIMS Articles

Coastal communities increasingly invest in natural and nature-based features (e.g., living shorelines) as a strategy to protect shorelines and enhance coastal resilience. Tidal marshes are a common component of these strategies because of their capacity to reduce wave energy and storm surge impacts. Performance metrics of restoration success for living shorelines tend to focus on how the physical structure of the created marsh enhances shoreline protection via proper elevation and marsh plant presence. These metrics do not fully evaluate the level of marsh ecosystem development. In particular, the presence of key marsh bivalve species can indicate the capability of the …

Spatiotemporal Distribution Of Phycotoxins And Their Co-Occurrence Within Nearshore Waters, Michelle D. Onofrio, Todd A. Egerton, Kimberly S. Reece, Sarah K.D. Pease, Marta P. Sanderson, William Jones Iii, Evan Yeargan, Amanda Roach, Caroline Dement, William G. Reay, Allen R. Place, Juliette L. Smith

VIMS Articles

Harmful algal blooms (HABs), varying in intensity and causative species, have historically occurred throughout the Chesapeake Bay, U.S.; however, phycotoxin data are sparse. The spatiotemporal distribution of phycotoxins was investigated using solid-phase adsorption toxin tracking (SPATT) across 12 shallow, nearshore sites within the lower Chesapeake Bay and Virginia's coastal bays over one year (2017-2018). Eight toxins, azaspiracid-1 (AZA1), azaspiracid-2 (AZA2), microcystin-LR (MC-LR), domoic acid (DA), okadaic acid (OA), dinophysistoxin-1 (DTX1), pectenotoxin-2 (PTX2), and goniodomin A (GDA) were detected in SPATT extracts. Temporally, phycotoxins were always present in the region, with at least one phycotoxin group (i.e., consisting of OA and …

Comparative Study Of The Hemolymph Microbiome Between Live And Recently Dead American Lobsters Homarus Americanus, Jibom Jung, Patrick M. Gillevet, Masoumeh Sikaroodi, Jamal Andrews, Bk Song, Jeffrey D. Shields

VIMS Articles

Lobsters and other crustaceans do not have sterile hemolymph. Despite this, little is known about the microbiome in the hemolymph of the lobster Homarus americanus. The purpose of this study was to characterize the hemolymph microbiome in lobsters. The lobsters were part of a larger study on the effect of temperature on epizootic shell disease, and several died during the course of the study, providing an opportunity to examine differences in the microbiomes between live and recently dead (1−24 h) animals. The hemolymph microbiomes of live lobsters was different from those in dead animals and both were different from the …

The Status Of Virginia’S Public Oyster Resource 2020, Melissa Southworth, Roger L. Mann

Reports

The Virginia Institute of Marine Science (VIMS) monitors recruitment of the Eastern oyster, Crassostrea virginica (Gmelin, 1791), annually from late spring through early fall, by deploying spatfall[1] (settlement and recruitment of larval oysters to the post metamorphic form termed spat) collectors (shellstrings) at various sites in three Virginia western Chesapeake Bay tributaries. The survey provides an estimate of a particular area’s potential for receiving a "strike" or settlement (set) of oysters on the bottom and helps describe the timing of recruitment events in a given year. Information obtained from this monitoring effort provides an overview of long-term recruitment …

Monitoring The Abundance Of American Shad And River Herring In Virginia’S Rivers 2020 Annual Report, Eric J. Hilton, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twenty-third year of a continuing study to estimate the relative abundance and assess the status of American shad (Alosa sapidissima) stocks in Virginia by monitoring the spawning runs in the James, York and Rappahannock rivers in spring 2020, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007, ASMFC 2020).

We also report on two fisheryindependent monitoring programs using anchor gillnets in the Rappahannock River (year 3) and the Chickahominy River (year 6; a major tributary of the James River), to determine relative abundance and stock structure for the adult spawning run of …

Rhodomonas Pe545 Fluorescence Is Increased By Glycerol, Chanoknard Karnjanapak, I-Shuo Huang, Preyanut Jaroensuk, Et Al

VIMS Articles

Phycobilins are photosynthetic pigments found in three ecologically important groups of algae: cyanobacte- ria, red algae, and cryptophytes. These compounds are covalently attached to proteins, which can be technically difficult to analyze compared with other photosynthetic pigments (e.g., chlorophylls and carotenoids). In this study, glycerol was demonstrated to uncouple PE545 (phycoerythrin 545), the phycobilin complex of Rhodomonas spp., from its role as a light-harvesting pigment: the fluorescence signal was increased 15–34 times, and ETR (electron transport rate) was no longer light-dependent at high light intensities. Glycerol induced fluorescence provided a simple and inexpensive protocol to ascertain the pool size of …

Seasonal Resource Pulses And The Foraging Depth Of A Southern Ocean Top Predator, Roxanne S. Beltran, A. Marm Kilpatrick, Greg A. Breed, (...), Walker O. Smith Jr., Et Al

VIMS Articles

Seasonal resource pulses can have enormous impacts on species interactions. In marine ecosystems, air-breathing predators often drive their prey to deeper waters. However, it is unclear how ephemeral resource pulses such as near-surface phytoplankton blooms alter the vertical trade-off between predation avoidance and resource availability in consumers, and how these changes cascade to the diving behaviour of top predators. We integrated data on Weddell seal diving behaviour, diet stable isotopes, feeding success and mass gain to examine shifts in vertical foraging throughout ice break-out and the resulting phytoplankton bloom each year. We also tested hypotheses about the likely location of …

Living Shorelines Achieve Functional Equivalence To Natural Fringe Marshes Across Multiple Ecological Metrics, Robert Isdell, Donna M. Bilkovic, Amanda Guthrie, Molly Mitchell, Randolph M. Chambers, Matthias Leu, Carl Hershner

VIMS Articles

Nature-based shoreline protection provides a welcome class of adaptations to promote ecological resilience in the face of climate change. Along coastlines, living shorelines are among the preferred adaptation strategies to both reduce erosion and provide ecological functions. As an alternative to shoreline armoring, living shorelines are viewed favorably among coastal managers and some private property owners, but they have yet to undergo a thorough examination of how their levels of ecosystem functions compare to their closest natural counterpart: fringing marshes. Here, we provide a synthesis of results from a multi-year, large-spatial-scale study in which we compared numerous ecological metrics (including …

Saved By The Shell: Oyster Reefs Can Shield Juvenile Blue Crabs Callinectes Sapidus, Katherine S. Longmire, Rochelle D. Seitz, Alison Smith, Romuald N. Lipcius

VIMS Articles

Juvenile blue crabs Callinectes sapidus use seagrass and other structured habitats as refuges from predation. Oyster reef habitats provide structural complexity that may offer refuge, but the value of these habitats for juvenile blue crabs has not been examined. We quantified survival of juvenile C. sapidus in structured oyster reef habitat versus unstructured soft-bottom habitat. In a field tethering experiment in the York River, lower Chesapeake Bay (USA), juvenile C.sapidus (10−50 mm carapace width [CW]) were tethered in sand (n = 40) or oyster reef (n = 39)habitats at subtidal sites 1−2 m deep. An underwater camera system was used …

Methods For Identifying Species Complexes Using A Novel Suite Of Multivariate Approaches And Multiple Data Sources: A Case Study With Gulf Of Alaska Rockfish, Kristen L. Omori, Cindy A. Tribuzo, Elizabeth A. Babcock, John M. Hoenig

VIMS Articles

International and national laws governing the management of living marine resources generally require specification of harvest limits. To assist with the management of data-limited species, stocks are often grouped into complexes and assessed and managed as a single unit. The species that comprise a complex should have similar life history, susceptibility to the fishing gear, and spatial distribution, such that common management measures will likely lead to sustainable harvest of all species in the complex. However, forming complexes to meet these standards is difficult due to the lack of basic biological or fisheries data to inform estimates of biological vulnerability …

Wap-1d-Var V1.0: Development And Evaluation Of A One-Dimensional Variational Data Assimilation Model For The Marine Ecosystem Along The West Antarctic Peninsula, Hyewon Heather Kim, Ya-Wei Luo, Hugh W. Ducklow, Oscar M. Schofield, Deborah K. Steinberg, Scott C. Doney

VIMS Articles

The West Antarctic Peninsula (WAP) is a rapidlywarming region, with substantial ecological and biogeochemical responses to the observed change and variability for the past decades, revealed by multidecadal observations
from the Palmer Antarctica Long-Term Ecological Research (LTER) program. The wealth of these long-term observations provides an important resource for ecosystem modeling, but there has been a lack of focus on the development of numerical models that simulate time-evolving plankton dynamics over the austral growth season along the coastal WAP. Here, we introduce a one dimensional variational data assimilation planktonic ecosystem model (i.e., the WAP-1D-VAR v1.0 model) equipped with a model …

The Expanding Role Of Natural History Collections, Eric J. Hilton, Gregory J. Watkins-Colwell, Sarah K. Huber

VIMS Articles

Museum specimens serve as the bedrock of systematic and taxonomic research and provide the basis for repeatability or reinterpretation of preserved aspects of phenotypes. Specimens are also fundamental to fields such as ecology, behavior, and development. Each specimen is a record of biodiversity and documents a particular species present at a particular place at a particular time. As such, specimens can provide key evidence for biodiversity and conservation initiatives. Four aspects of natural history collections and their use are discussed here: 1) collection, curation, and use of specimens, particularly non-traditional specimens; 2) the use of specimens and technological advances in …

Distinguishing Zooplankton Fecal Pellets As A Component Of The Biological Pump Using Compound-Specific Isotope Analysis Of Amino Acids, S. C. Doherty, A. E. Maas, Deborah K. Steinberg, B. N. Popp, H. G. Close

VIMS Articles

Zooplankton contribute a major component of the vertical flux of particulate organic matter to the ocean interior by packaging consumed food and waste into large, dense fecal pellets that sink quickly. Existing methods for quantifying the contribution of fecal pellets to particulate organic matter use either visual identification or lipid biomarkers, but these methods may exclude fecal material that is not morphologically distinct, or may include zooplankton carcasses in addition to fecal pellets. Based on results from seven pairs of wild-caught zooplankton and their fecal pellets, we assess the ability of compound-specific isotope analysis of amino acids (CSIA-AA) to chemically …

Role Of Food Web Interactions In Promoting Resilience To Nutrient Enrichment In A Brackish Water Eelgrass (Zostera Marina) Ecosystem, K. Gagnon, C. Gustafsson, (...), J. P. Richardson, P. L. Reynolds, J. E. Duffy, C. Boström

VIMS Articles

Understanding the ecological interactions that enhance the resilience of threatened ecosystems is essential in assuring their conservation and restoration. Top-down trophic interactions can increase resilience to bottom-up nutrient enrichment, however, as many seagrass ecosystems are threatened by both eutrophication and trophic modifications, understanding how these processes interact is important. Using a combination of approaches, we explored how bottom-up and top-down processes, acting individually or in conjunction, can affect eelgrass meadows and associated communities in the northern Baltic Sea. Field surveys along with fish diet and stable isotope analyses revealed that the eelgrass trophic network included two main top predatory fish …

Molecular Underpinnings And Biogeochemical Consequences Of Enhanced Diatom Growth In A Warming Southern Ocean, L.J. Jabre, A.E Allen, S.J.P. Mccain, (...), Rachel E. Sipler, Et Al

VIMS Articles

Phytoplankton contribute to the Southern Ocean’s (SO) ability to absorb atmospheric CO₂ and shape the stoichiometry of northward macronutrient delivery. Climate change is altering the SO environment, yet we know little about how resident phytoplankton will react to these changes. Here, we studied a natural SO community and compared responses of two prevalent, bloom-forming diatom groups to changes in temperature and iron that are projected to occur by 2100 to 2300. We found that one group, Pseudo-nitzschia, grows better under warmer low-iron conditions by managing cellular iron demand and efficiently increasing photosynthetic capacity. This ability to grow and …

Effect Of Environmental History On The Physiology And Acute Stress Response Of The Eastern Oyster Crassostrea Virginica, Jill Ashey, Emily B. Rivest

VIMS Articles

Environmental history (regimes of water quality to which an organism has been exposed in the past) may influence how the physiology of eastern oysters Crassostrea virginica responds to future environmental conditions caused by climate change. Previous research has examined environmental history in a 1-dimensional framework, failing to capture environmental history complexity through space and time. In this study, we examined environmental history as a multi-faceted parameter, incorporating abiotic water quality components, such as temperature, pH, and salinity, that differ among locations. We also assessed how different lengths of environmental histories, defined as proximal and distal, affected oyster physiology and stress …

A Taxonomic Review Of The Family Trachipteridae (Lampridiformes), With An Emphasis On Taxa Distributed In The Western Pacific Ocean, Jennifer Martin, Eric J. Hilton

VIMS Articles

The family Trachipteridae—the Ribbonfishes, Dealfishes, and their relatives—has a circumglobal distribution, with at least 10 species in three genera (Zu Walters & Fitch 1960, Desmodema Walters & Fitch 1960, and Trachipterus Goüan 1770) that are characterized by elongate, extremely laterally compressed bodies, large eyes, absence of ribs, spines on lateral-line scales, greatly protrusible mouths, and a lack of pelvic fins in adults. They are also known for the drastic morphological changes that occur during ontogeny. Trachipterids are poorly represented in collections due to the fragile nature of their bodies. Most studies of the Trachipteridae have been limited by the …

A Review Of How We Assess Denitrification In Oyster Habitats And Proposed Guidelines For Future Studies, Nicholas E. Ray, Boze Hancock, Mark J. Brush, Allison Colden, (...), M. Lisa Kellogg, Et Al

VIMS Articles

Excess nitrogen (N) loading and resulting eutrophication plague coastal ecosystems globally. Much work is being done to remove N before it enters coastal receiving waters, yet these efforts are not enough. Novel techniques to remove N from within the coastal ecosystem are now being explored. One of these techniques involves using oysters and their habitats to remove N via denitrification. There is substantial interest in incorporating oyster-mediated enhancement of benthic denitrification into N management plans and trading schemes. Measuring denitrification, however, is expensive and time consuming. For large-scale adoption of oyster-mediated denitrification into nutrient management plans, we need an accurate …

Bioaccumulation Of Pcbs, Ocps And Pbdes In Marine Mammals From West Antarctica, Mohammed Khairy, Emily Brault, Rebecca Dickhut, Et Al

VIMS Articles

To understand the bioaccumulation and food web dynamics of persistent organic pollutants (POPs) as a function of species, age and sex in Antarctic mammals, blubber samples of 3 killer whales (Type C) and 77 pinnipeds (Weddell, Ross and crabeater seals) were collected from the Southern Ocean, Antarctica. They were analyzed for polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and polybrominated diphenyl ethers (PBDEs). ΣDDTs, Σ₂₉PCBs and chlordanes (12 – 4,600, 13 – 1,600, and < 1.5 – 1,700 ng/g lipid, respectively) were the most abundant POPs. Killer whales typically displayed several times greater concentrations of POPs compared to seals, except for PBDEs. PCBs and PBDEs were consistently higher in adult crabeater and Weddell seal males, and in adult female Ross seals than in other sex and age groups reflecting an age accumulation and possible influence of segregated diet, foraging areas, and metabolic transformation rates. POPs concentrations significantly correlated with gene transcription of nuclear receptors involved in detoxification of contaminants and immune relevant cell mediators in the crabeater seals, indicating possible immunotoxic and deleterious health effects. This represents one of the largest studies on POPs in Antarctic marine predators and highlights the complexity of POPs bioaccumulation.

Seabed Resuspension In The Chesapeake Bay: Implications For Biogeochemical Cycling And Hypoxia, Julia M. Moriarty, Marjorie A.M. Friedrichs, Courtney K. Harris

VIMS Articles

Sediment processes, including resuspension and transport, affect water quality in estuaries by altering light attenuation, primary productivity, and organic matter remineralization, which then influence oxygen and nitrogen dynamics. The relative importance of these processes on oxygen and nitrogen dynamics varies in space and time due to multiple factors and is difficult to measure, however, motivating a modeling approach to quantify how sediment resuspension and transport affect estuarine biogeochemistry. Results from a coupled hydrodynamic-sediment transport-biogeochemical model of the Chesapeake Bay for the summers of 2002 and 2003 showed that resuspension increased light attenuation, especially in the northernmost portion of the Bay, …

Opportunities And Challenges For Including Oyster-Mediated Denitrification In Nitrogen Management Plans, Julie M. Rose, J. Stephen Gosnel, Suzanne Bricker, Mark J. Brush, Allison Colden, Et Al

VIMS Articles

Nitrogen pollution is one of the primary threats to coastal water quality globally, and governmental regulations and marine policy are increasingly requiring nitrogen remediation in management programs. Traditional mitigation strategies (e.g., advanced wastewater treatment) are not always enough to meet reduction goals. Novel opportunities for additional nitrogen reduction are needed to develop a portfolio of long-term solutions. Increasingly, in situ nitrogen reduction practices are providing a complementary management approach to the traditional source control and treatment, including recognition of potential contributions of coastal bivalve shellfish. While policy interest in bivalves has focused primarily on nitrogen removal via biomass harvest, bivalves …