Aquaculture and Fisheries Commons^™

Estimating Shifts In Phenology And Habitat Use Of Cobia In Chesapeake Bay Under Climate Change, Daniel P. Crear, Brian E. Watkins, Marjorie A.M. Friedrichs, Pierre St-Laurent, Kevin C. Weng

VIMS Articles

Cobia (Rachycentron canadum) is a large coastal pelagic fish species that represents an important fishery in many coastal Atlantic states of the U.S. They are heavily fished in Virginia when they migrate into Chesapeake Bay during the summer to spawn and feed. These coastal habitats have been subjected to warming and increased hypoxia which in turn could impact the timing of migration and the habitat suitability of Chesapeake Bay. With conditions expected to worsen, we project current and future habitat suitability of Chesapeake Bay for cobia and predict changes in their arrival and departure times as conditions shift. To do …

The Power Struggle: Assessing Interacting Global Change Stressors Via Experimental Studies On Sharks, Ian A. Bouyoucos, Sue-Ann Watson, Serge Planes, Colin A. Simpfendorfer, Gail D. Schwieterman, Et Al

VIMS Articles

Ocean warming and acidification act concurrently on marine ectotherms with the potential for detrimental, synergistic effects; yet, effects of these stressors remain understudied in large predatory fishes, including sharks. We tested for behavioural and physiological responses of blacktip reef shark (Carcharhinus melanopterus) neonates to climate change relevant changes in temperature (28 and 31 °C) and carbon dioxide partial pressures (pCO₂; 650 and 1050 µatm) using a fully factorial design. Behavioural assays (lateralisation, activity level) were conducted upon 7–13 days of acclimation, and physiological assays (hypoxia tolerance, oxygen uptake rates, acid–base and haematological status) were …

Identifying Important Juvenile Dusky Shark Habitat In The Northwest Atlantic Ocean Using Acoustic Telemetry And Spatial Modeling, Charles W. Bangley, Tobey H. Curtis, David H. Secor, Robert J. Latour, Matthew B. Ogburn

VIMS Articles

Highly mobile species can be challenging for fisheries management and conservation due to large home ranges combined with dependence on discrete habitat areas where they can be easily targeted or vulnerable to anthropogenic disturbances. Management of the Dusky Shark Carcharhinus obscurus in the northwest Atlantic Ocean has been particularly challenging due to the species' inherent vulnerability to overfishing and poorly understood habitat associations. To better understand habitat associations and seasonal distributions, we combined telemetry and remotely sensed environmental data to spatially model juvenile Dusky Shark presence probability in the northwest Atlantic Ocean. To accomplish this, 22 juvenile Dusky Sharks (107-220 …

Virginia Wild-Caught Blue Catfish: Nutrition And Contaminant Analysis, Robert A. Fisher

Reports

The blue catfish, Ictalurus furcatus, is an introduced freshwater species in Virginia’s tributaries to the Chesapeake Bay. Since its introduction in the 1970’s, significant recreational and commercial fisheries have developed within upriver, largely freshwater environments. Blue catfish are voracious, opportunistic predators, feeding on a variety of natural prey items, including native fish and shellfish species. Their varied diets result in a more nutrient-rich fish compared to farmraised catfish (USDA Food and Nutrient Database https://fdc.nal.usda.gov/fdc-app. html#/?query=catfish) on the market, which are typically fed a plant-based diet.

In recent years, blue catfish populations have expanded from upriver freshwater habitat to major brackish-water …

Improving Production Of The Eastern Oyster Crassostrea Virginica Through Coordination Of Genetic Improvement Programs, Research, And Technology Transfer Activities, Standish K. Allen Jr., Caird Rexroad Iii, Robert Rheault

VIMS Articles

The East Coast Shellfish Growers Association has been actively advocating for continued improvement of breeding infrastructure to support a vibrant and ecologically crucial industry. This white paper acknowledges these efforts and is meant to serve as a paradigm for oyster breeding on the East Coast. The vision is relatively straightforward; however, its execution—like most things—will be fraught with detail and inertia. Yet describing simply the idea without articulating some detail and potential roadblocks would be misleading. Instead, we present a picture of a breeding paradigm as it might play out across the entire range of a species. At this particular …

Virginia Game Fish Tagging Program Annual Report 2019, Susanna Musick, Lewis Gillingham

Reports

Through 2019, the Virginia Game Fish Tagging Program (VGFTP) has maintained a 24-year database of records for tagged and recaptured fish. The program is a cooperative project of the Virginia Saltwater Fishing Tournament (VSFT) under the Virginia Marine Resources Commission-(VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under the VIMS Marine Advisory Program).

Estimation Of Juvenile Striped Bass Relative Abundance In The Virginia Portion Of Chesapeake Bay Annual Progress Report: 2019 - 2020, Jack R. Buchanan, Troy D. Tuckey, Mary C. Fabrizio

Reports

The 2019 Striped Bass juvenile abundance index was 9.54 and was not significantly different than the reference mean of 7.77 from 1980-2009. Abundance indices in the James, York, and Rappahannock rivers in 2019 were average compared with their individual reference means (1980-2009). Relatively low catches of young‐of‐the‐year Striped Bass from sites upriver and downriver of core nursery areas suggest Striped Bass largely remained within core nursery areas in 2019. Juvenile White Perch abundance indices in 2019 were above historic averages in the James, York and Rappahannock river systems.

Juvenile abundance indices for Atlantic Croaker, Alewife, Spot, and Atlantic Silverside were …

In The Face Of Climate Change And Exhaustive Exercise: The Physiological Response Of An Important Recreational Fish Species, Daniel P. Crear, Richard Brill, Lauren M.L. Averilla, Sara C. Meakem, Kevin C. Weng

VIMS Articles

Cobia (Rachycentron canadum) support recreational fisheries along the US mid- and south-Atlantic states and have been recently subjected to increased fishing effort, primarily during their spawning season in coastal habitats where increasing temperatures and expanding hypoxic zones are occurring due to climate change. We therefore undertook a study to quantify the physiological abilities of cobia to withstand increases in temperature and hypoxia, including their ability to recover from exhaustive exercise. Respirometry was conducted on cobia from Chesapeake Bay to determine aerobic scope, critical oxygen saturation, ventilation volume and the time to recover from exhaustive exercise under temperature and …

Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2019 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twenty-second 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 2019, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007). We also report on two fishery-independent monitoring programs using anchor gillnets in the Rappahannock River (year 2) and the Chickahominy River (year 5; a major tributary of the James River), to determine relative abundance and stock structure for the adult spawning run of river herring …

Population Structure Of The Blue Crab Callinectes Sapidus In The Maryland Coastal Bays, Kristen A. Lycett, Jeffrey D. Shields, J. Sook Chung, Joseph S. Pitula

VIMS Articles

The population structure of the blue crab Callinectes sapidus was examined in the Maryland Coastal Bays (MCB) from 2014 to 2016. Crabs were sampled from April to December of each year. Size–frequency distributions showed a strong seasonal cycle, with small crabs being abundant in April, increasing in size through September, with adult crabs observed in the highest proportions from August through October of each year. A subsample of crabs was assayed for hemolymph ecdysone concentrations to examine molting patterns in field-collected blue crabs. Molting was observed throughout the sampling season, peaking in April for immature crabs, with lows in all …

Alternative Substrates Used For Oyster Reef Restoration: A Review, Taylor Goelz, Bruce Vogt, Troy W. Hartley

VIMS Articles

Oyster populations and reef habitats have notably declined in the last century around the world. The ecological, economic, and cultural values of oysters have led to a variety of restoration efforts seeking to recover these lost benefits. Limitations of the native oyster shell substrate and the large-scale nature of many restoration projects have resulted in the increased use of a variety of alternative, or artificial, substrates to create reef structures. A text mining package was used to conduct a review of alternative substrates used for oyster restoration. Specifically, the review (1) assessed commonly used alternative substrates, (2) locations where alternative …

Targeted “Hotspot” Removal Of Derelict Blue Crab Traps (Va, Md), Kirk J. Havens, Donna Marie Bilkovic, David Stanhope, Kory Angstadt, Andrew M. Scheld

Reports

In the winter of 2019/2020, five commercial watermen spent a cumulative total of 120 removal days on the water and collected 971 derelict blue crab traps which contained 985 blue crabs, 239 fish (oyster toad fish, black sea bass, flounder, pig fish, striped bass, speckled trout, perch, butterfish), 31 diamond back terrapin (a listed “species of concern”), and one duck. A majority of the traps removed were metal as opposed to vinyl coated (83% and 17%, respectively). Bycatch was present in 43% (346) of metal traps and 44% (72) of vinyl coated traps removed. On average, the instantaneous capture rates …

Dichotomous Keys: An Essential Tool For Fish Detectives, Jackson Martinez

Reports

Grades: 6-8 Subjects: Life Science | Biology

How do scientists identify an unknown fish?

In this activity, students will utilize a dichotomous key to identify unknown fishes from the Chesapeake Bay and will then characterize their trophic levels based on feeding preferences and adaptations. Students will gain an understanding of organism classification, trophic level interactions, and how fishes may play different trophic roles throughout their lives.

A Mechanistic Understanding Of Range Expansion Of Invasive Blue Catfish In The Chesapeake Bay Region, Vaskar Nepal

Dissertations, Theses, and Masters Projects

Blue catfish Ictalurus furcatus is an invasive species of great concern in coastal habitats throughout the eastern United States, inclulding the Chesapeake Bay and its tributaries. In this dissertation, I use field surveys, laboratory experiments and quantitative modeling to provide insights into several aspects of blue catfish biology at the individual level. In chapter 1, I characterize and compare patterns in growth and body condition in blue catfish populations in the James and York river subestuaries during two stages of invasion. Both the mean growth rate and mean body condition of blue catfish declined in the recent period in response …

Predicting The Impacts Of Climate Change On The Sandbar Shark And Cobia, Daniel P. Crear

Dissertations, Theses, and Masters Projects

A changing climate has been identified as a major driver of changes in marine species’ distribution, phenology, and habitat selection in recent decades and is expected to continue to influence these traits. These changes are not only happening in our oceans, but within coastal habitats as well, where waters are susceptible to sudden changes in temperature and oxygen levels are influenced by nutrient inputs. These changes which will likely impact fish species that utilize these areas as nurseries, spawning habitat, or foraging grounds. In this dissertation I consider climate impacts on two important predators, the sandbar shark (Carcharhinus plumbeus) and …

Morphology And Systematics Of Batrachoidiformes (Percomorphacea: Teleostei), Diego Francisco Biston Vaz

Dissertations, Theses, and Masters Projects

Batrachoidiformes, the toadfishes, are benthic fishes that inhabit nearshore subtidal and intertidal habitats, characterized by their dorsoventrally flattened bodies and large pectoral fins. These fishes lack dispersive larvae, and larval development is retained in nests guarded by their parents. To date, 82 species and 23 genera are accepted as valid. Previous studies recognized a single family, Batrachoididae, with four subfamilies: Batrachoidinae, Porichthyinae, Thalassophryninae, and Halophryninae. Interrelationships among subfamilies, however, are unresolved and interrelationships among species are problematic. Despite being a conspicuous member of the coastal fauna, the internal morphology of most species of Batrachoidiformes is unknown, being intraspecific and ontogenetic …

Temporal, Spatial, And Biological Variation Of Nematode Epidemiology In American Eels, Zt Warshafsky, Troy D. Tuckey, Wk Vogelbein, Rj Latour, Ar Wargo

VIMS Articles

This is the accepted manuscript version of the article.

American eels (Anguilla rostrata) are infected by the non-native parasitic nematode Anguillicoloides crassus, which can cause severe swim bladder damage. We investigated epidemiology of A. crassus to better understand its population-level effects on American eels. Nematode prevalence, abundance, and intensity and swim bladder damage were quantified in glass eels, elvers, and yellow eels from the lower Chesapeake Bay and related to season of capture, river system, and total length. Age-variant force-of-infection and disease-associated mortality were estimated using a three-state irreversible disease model, which assumes recovery is not possible. Results showed glass …

A Data Repository For Minimal Effects Of Oyster Aquaculture On Water Quality: Examples From Southern Chesapeake Bay, Jessica Turner, Grace M. Massey, M. Lisa Kellogg, Carl Friedrichs

Data

The objective of this study was to quantify the effects of oyster aquaculture on water quality, sediment quality, and hydrodynamics at select sites in southern Chesapeake Bay. To this end, information was gathered over the course of approximately one year from February 2017 to October 2017 at four operating commercial farms. Farms were sampled during spring, summer, and fall seasons during times of oyster filtration activity when temperatures were greater than 10^oC. Aquaculture sites differed in environmental setting, in terms of their exposure to waves and resulting sediment characteristics. Sites had mesohaline salinities (ranging from 15-22 psu) and …

Oyster Reef Ecosystem Services: Finfish Utilization And Trophic Linkages Harris Creek, Maryland, Usa, M. Lisa Kellogg, Paige G. Ross, Manisha Pant, Jennifer C. Dreyer, Alan Birch, Sean Fate, Edward Smith

Reports

Oyster reefs provide habitat for finfish and their prey. Our project focused on determining the impacts of oyster reef restoration on finfish in the Harris Creek Oyster Sanctuary in the Maryland portion of Chesapeake Bay. As a preliminary step, we examined the utility of using trawls in the place of gillnets to sample finfish but found that trawl samples were also highly variable and that the diets of finfish caught in trawls tended to be different than those caught in gillnets. Based on these findings and the fact that gillnets can be set within reef habitats, all remaining sampling was …

Quantifying Habitat Selection And Variability In Habitat Suitability For Juvenile White Sharks, Cf White, K Lyons, Sj Jorgensen, J O'Sullivan, C Winkler, Kevin C. Weng, Cg Lowe

VIMS Articles

While adult white sharks (Carcharodon carcharias) are apex predators with a circumglobal distribution, juvenile white sharks (JWS) feed primarily on bottom dwelling fishes and tend to be coastally associated. Despite the assumedly easier access to juveniles compared to large, migratory adults, limited information is available on the movements, environments, and distributions of individuals during this life stage. To quantify movement and understand their distribution in the southern California Bight, JWS were captured and fitted with dorsal fin-mounted satellite transmitters (SPOT tags; n = 18). Nine individuals crossed the U.S. border into Baja California, Mexico. Individuals used shallow habitats (134.96 +/- …

Virginia Game Fish Tagging Program Annual Report 2018, Susanna Musick, Lewis Gillingham

Reports

Through 2018, the Virginia Game Fish Tagging Program (VGFTP) has maintained a 23-year database of records for tagged and recaptured fish. The program is a cooperative project of the Virginia Saltwater Fishing Tournament (VSFT) under the Virginia Marine Resources Commission-(VMRC) and the Virginia Institute of Marine Science (VIMS) of the College of William and Mary (under the VIMS Marine Advisory Program).

Monitoring The Abundance Of American Shad And River Herring In Virginia's Rivers - 2018 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

This report describes the results of the twenty-first 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 2018, evaluating hatchery programs, and contributing to coast-wide assessments (ASMFC 2007). We also report on two fishery-independent monitoring programs using anchor gillnets in the Rappahannock River (year 1) and the Chickahominy River (year 4; a major tributary of the James River), to determine relative abundance and stock structure for the adult spawning run of river herring …

Estimating Relative Abundance Of Young-Of-The-Year American Eel, Anguilla Rostrata, In The Virginia Tributaries Of Chesapeake Bay, Spring 2018, Troy D. Tuckey, Mary C. Fabrizio

Reports

American Eel (Anguilla rostrata) is a valuable commercial species along the Atlantic coast of North America from New Brunswick to Florida. In the U.S., harvests have declined, with similar patterns occurring in the Canadian Maritime Provinces (Meister and Flagg 1997). An average of 62% of the annual landings of U.S. commercial harvest since 1993 have come from the Chesapeake Bay (personal communication from the National Marine Fisheries Service, Fisheries Statistics Division, 9 February 2015). In 2013, Virginia commercial landings were approximately 100,298 lbs; since mandatory reporting began in 1993, average annual landings in Virginia have been 193,200 lbs or 19% …

Climate Change Enhances Disease Processes In Crustaceans: Case Studies In Lobsters, Crabs, And Shrimps, Jeffrey D. Shields

VIMS Articles

Climate change has resulted in increasing temperature and acidification in marine systems. Rising temperature and acidification act as stressors that negatively affect host barriers to infection, thus enhancing disease processes and influencing the emergence of pathogens in ecologically and commercially important species. Given that crustaceans are ectotherms, changes in temperature dominate their physiological and immunological responses to microbial pathogens and parasites. Because of this, the thermal ranges of several crustacean hosts and their pathogens can be used to project the outcomes of infections. Host factors such as molting, maturation, respiration, and immune function are strongly influenced by temperature, which in …

Tracking Triploid Mortalities Of Eastern Oysters Crassostrea Virginica In The Virginia Portion Of The Chesapeake Bay, Eric Guevelou, Ryan Carnegie, Ja Moss, Karen Hudson, Kimberly S. Reece, Molly M. Rybovich, Standish K. Allen Jr.

VIMS Articles

Since 2012, aquacultured eastern oysters Crassostrea virginica have been reported by oyster farmers to display mortality approaching 30%, and in some cases 85%, in areas of the lower Chesapeake Bay, VA. Based on accounts from industry, this mortality has typically affected 1-y-old oysters between May and early July, and has tended to occur in triploid oysters, which represent the vast bulk of production in the area. During this period, samples submitted for pathology have not revealed the presence of major pathogens as a cause. In 2015, to gain deeper insight into this mortality and determine whether specific sites, ploidy condition, …

Nursery Habitat Quality Assessed By The Condition Of Juvenile Fishes: Not All Estuarine Areas Are Equal, Ryan W. Schloesser, Mary C. Fabrizio

VIMS Articles

High-quality nursery habitats support greater numbers of juveniles that survive to adulthood, but characteristics underlying high-quality habitats remain elusive because their productivity varies spatially and temporally and may be species-specific. Fish condition is an energy-integrative measure of ecological interactions, stress, and activity within a habitat, such that juvenile fish condition is representative of the quality of nursery habitats. We apply spatially explicit models to examine patterns in nursery habitat quality of Virginia estuaries based on nutritional condition for Atlantic croaker Micropogonias undulatus, summer flounder Paralichthys dentatus, and striped bass Morone saxatilis. Environmental factors (water temperature, dissolved oxygen, salinity, and depth) …

Estimation Of Juvenile Striped Bass Relative Abundance In The Virginia Portion Of Chesapeake Bay. Annual Progress Report: 2018-2019, Brian K. Gallagher, Mary C. Fabrizio, Troy D. Tuckey

Reports

The 2018 Striped Bass juvenile abundance index was 10.72 and was not significantly different than the reference mean of 7.77 from 1980-2009. Abundance indices in the James and York river systems in 2018 were average compared to their individual reference means (1980-2009), whereas abundance was above average in the Rappahannock River. Relatively high catches of young‐of‐the‐year Striped Bass at downriver sites in 2018 suggested Striped Bass were displaced downstream of their typical core nursery areas, likely due to high volumes of freshwater discharge and low salinities before and during the sampling period. Juvenile White Perch abundance indices in 2018 were …

Satellites, Seagrass, And Blue Crabs: Understanding Inter-Annual Fluctuations And Linkages In The York River, Kristen Bachand

Dissertations, Theses, and Masters Projects

To protect and manage ecosystems over large spatial scales, repeated mapping with remote sensing, such as aerial photography, is valuable, but several potential problems need to be overcome to generate accurate maps. For instance, to monitor submerged aquatic vegetation (SAV), such as seagrass, satellite imagery must often capture seasonal and interannual variation as well as disturbances. We used a model system, SAV and the blue crab Callinectes sapidus in the lower Chesapeake Bay, to examine (i) if Planet Lab (PL) satellite imagery can be used to accurately estimate SAV coverage by comparing PL images coincident with those of the VIMS …

Assessment Of The Relationship Of Stock And Recruitment In The Atlantic Surfclam Spisula Solidissima In The Northwestern Atlantic Ocean, Jeremy R. Timbs, Eric N. Powell, Roger L. Mann

VIMS Articles

Atlantic surfclams support a major commercial fishery in the western North Atlantic Ocean with landings consistently between 15,000 and 25,000 metric tons since 1982. The stock is not and historically has not been overfished nor has overfishing occurred; however, in recent years landings per unit effort have declined. Surfclams are a biomass dominant on the continental shelf and a bellwether of climate change in the northwestern Atlantic. This study investigated the relationship of broodstock and recruitment during a period when Mid-Atlantic warming initiated a shelf-wide shift in the surfclams range. A species distribution function model was used to assess the …

Rising Temperatures, Molting Phenology, And Epizootic Shell Disease In The American Lobster, Maya Groner, Jeffrey D. Shields, Df Landers, J Swenarton, Jm Hoenig

VIMS Articles

Phenological mismatchmaladaptive changes in phenology resulting from altered timing of environmental cuesis an increasing concern in many ecological systems, yet its effects on disease are poorly characterized. American lobster (Homarus americanus) is declining at its southern geographic limit. Rising seawater temperatures are associated with seasonal outbreaks of epizootic shell disease (ESD), which peaks in prevalence in the fall. We used a 34-year mark-recapture data set to investigate relationships between temperature, molting phenology, and ESD in Long Island Sound, where temperatures are increasing at 0.4 degrees C per decade. Our analyses support the hypothesis that phenological mismatch is linked to the …