Digital Commons Network^™

Hard-Bottom Habitats Support Commercially Important Fish Species: A Systematic Review For The North Atlantic Ocean And Baltic Sea, Hugo Flávio, Rochelle D. Seitz, David Eggleston, Jon C. Svendsen, Josianne Støttrup

VIMS Articles

Hard-bottom habitats span a range of natural substrates (e.g., boulders, cobble) and artificial habitats (e.g., the base of wind turbines, oil platforms). These hard-bottom habitats can provide a variety of ecosystem services, ranging from the enhancement of fish biomass and production to providing erosion control. Management decisions regarding the construction or fate of hard-bottom habitats require information on the ecological functions of these habitats, particularly for species targeted in ecosystem-based fisheries management. This study provides a systematic review of the relationships of various hard-bottom habitats to individual commercially harvested species that are managed jointly across the Atlantic by the International …

Succession Of The Late Summer Phytoplankton Blooms In The York River Estuary, Va, Heather Kathleen Corson

Dissertations, Theses, and Masters Projects

The influence of bottom-up and top-down controls on the formation and persistence of phytoplankton blooms has been well studied. However, the relative importance of these bottom-up and top-down controls vary spatially and temporally. In the tidal tributaries and mainstem of Chesapeake Bay, the summer dinoflagellate population follows a succession of bloom-producing species. The dinoflagellate species Margalefidinium polykrikoides and Alexandrium monilatum are currently considered the end of this succession. These species form near-annual blooms in the lower half of Chesapeake Bay and are considered harmful algal bloom (HAB) species due to their negative ecological impacts. However, analysis of long-term monitoring data …

Empirical Valuation Of Primary And Alternative Nursery Habitats For The Blue Crab Callinectes Sapidus In Chesapeake Bay, Alexander C. Hyman

Dissertations, Theses, and Masters Projects

The blue crab (Callinectes sapidus) is a commercially and ecologically importantspecies found along the Atlantic coast of North and South America. These crustaceans play a critical role in coastal ecosystems, serving as both predators and prey in the food web. The blue crab supports a major fishery in Chesapeake Bay, where the species is a cultural icon. Juvenile blue crabs, the smallest and most vulnerable size classes of individuals, are reliant upon structurally complex habitats. Population dynamics of this species are therefore influenced by spatiotemporally fluctuating environmental variables, such as habitat availability. Understanding blue crab ecology is essential for managing …

Age Based Assessment In The Sea Scallop Placopecten Magellanicus: A Pilot Study - Final Report, Roger L. Mann, David Rudders, Sally Roman, Melissa Southworth, Kaitlyn R. Clark

Reports

If the current sea scallop fishery is well managed with a Catch At Size Analysis (CASA) length structured model, then why bother with an age based assessment? The success of the CASA based approach, in conjunction with management measures, is demonstrated by the development of the scallop fishery over the past two decades to its current status as the one of the most valuable fisheries on the Atlantic coast of the United States (NOAA, 2021). But, even the best length-based model can be improved by the addition of age data. An age-based model calibrates a length-based model, including a description …

Analysis Of Edna To Assess Effects Of Water Quality On Freshwater Fungal Diversity In A Virginia Coastal Watershed, Lauren French

Undergraduate Honors Theses

Freshwater fungi comprise a phylogenetically and functionally diverse group which contributes to wide-ranging ecosystem processes in aquatic systems. Saprotrophic fungi convert detritus into nutrient-rich food sources for fish and invertebrates, whereas pathogenic and parasitic fungi can cause disease and population declines of other aquatic organisms. With their diverse and important roles, changes in freshwater fungal community structure may have far-reaching impacts on ecosystems. To understand how natural and anthropogenic stressors to freshwater systems impact fungal-mediated ecosystem processes, a greater understanding of the taxonomic and functional composition of freshwater fungal communities is needed. We assessed relationships among freshwater habitat types, water …

Emotion, Place, And Practice: Exploring The Interplay In Children's Engagement In Ecologists' Sampling Practices, Kathryn Lanouette

School of Education Articles

In science education, there has been a sustained focus on supporting the emergence of science practices in K–12 and field-based settings. Recent work has elevated the integral role of emotion in sparking and sustaining such disciplinary practices, deepening the field's understanding of what is entailed in “doing” science. Yet even as we gain this richer understanding of practice, less attention has been given to the places where practice emerges. These places play a critical role in the co-emergence of emotion and practice, and while separate strands of research have elevated emotion and practice or, alternately, place and practice, rarely has …

Spatiotemporal Modeling Of Nursery Habitat Using Bayesian Inference: Environmental Drivers Of Juvenile Blue Crab Abundance, A. Challen Hyman, Grace S. Chiu, Mary C. Fabrizio, Rom Lipcius

VIMS Articles

Nursery grounds provide conditions favorable for growth and survival of juvenile fish and crustaceans through abundant food resources and refugia, and enhance secondary production of populations. While small-scale studies remain important tools to assess nursery value of structured habitats and environmental factors, targeted applications that unify survey data over large spatial and temporal scales are vital to generalize inference of nursery function, identify highly productive regions, and inform management strategies. Using 21 years of spatio-temporally indexed survey data (i.e., water chemistry, turbidity, blue crab, and predator abundance) and GIS information on potential nursery habitats (i.e., seagrass, salt marsh, and unvegetated …

A Biologging Database Of Juvenile White Sharks From The Northeast Pacific, J. O'Sullivan, C. G. Lowe, (...), Kevin C. Weng, Et Al

VIMS Articles

Species occurrence records are vital data streams in marine conservation with a wide range of important applications. From 2001–2020, the Monterey Bay Aquarium led an international research collaboration to understand the life cycle, ecology, and behavior of white sharks (Carcharodon carcharias) in the southern California Current. The collaboration was devoted to tagging juveniles with animal-borne sensors, also known as biologging. Here we report the full data records from 59 pop-up archival (PAT) and 20 smart position and temperature transmitting (SPOT) tags that variously recorded pressure, temperature, and light-level data, and computed depth and geolocations for 63 individuals. Whether transmitted or …

Marine Heatwaves In The Chesapeake Bay, Piero L. F. Mazzini, Cassia Pianca

VIMS Articles

Prolonged events of anomalously warm sea water temperature, or marine heatwaves (MHWs), have major detrimental effects to marine ecosystems and the world's economy. While frequency, duration and intensity of MHWs have been observed to increase in the global oceans, little is known about their potential occurrence and variability in estuarine systems due to limited data in these environments. In the present study we analyzed a novel data set with over three decades of continuous in situ temperature records to investigate MHWs in the largest and most productive estuary in the US: the Chesapeake Bay. MHWs occurred on average twice per …

Environmental Ecology And Life History Variation Of Perkinsus Marinus, Lydia M. Bienlien

Dissertations, Theses, and Masters Projects

Marine resources provide a growing world population with the opportunity to increase food security, particularly through aquaculture. Oysters are prominent aquacultured species, but marine diseases are a threat to the growth and sustainability of oyster culture. Perkinsus marinus is the most important oyster pathogen of the Atlantic and Gulf coasts of the U.S., where it causes substantial mortality. Despite being one of the most well-studied protozoan parasites of bivalve molluscs, much is still unknown about P. marinus. This research investigated multiple characteristics of P. marinus.In Chapter Two, the environmental ecology of P. marinus was explored through tidal sampling and year-long …

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 …

Environmental Associations Of Cownose Ray (Rhinoptera Bonasus) Seasonal Presence Along The U.S. Atlantic Coast, Charles W. Bangley, Michelle L. Edwards, Claire Mueller, Robert A. Fisher, Et Al

VIMS Articles

Identifying the mechanistic drivers of migration can be crucial in shaping conservation and management policies. The cownose ray (Rhinoptera bonasus) is a relatively poorly understood elasmobranch species that occurs along the U.S. Atlantic coast and undergoes large-scale seasonal migrations. To better understand the drivers and timing of cownose ray seasonal migration in order to inform potential management measures, we analyzed telemetry detections of 51 mature cownose rays (38 female, 13 male) tagged with acoustic transmitters in the Maryland and Virginia portions of Chesapeake Bay. Detections within their summer habitat in Chesapeake Bay and winter habitat in the vicinity …

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 …

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 …

Bacterial And Archaeal Specific-Predation In The North Atlantic Basin, Lm Seyler, S Tuorto, Lr Mcguinness, Dl Gong, Lj Kerkof

VIMS Articles

Stable isotope probing (SIP) was used to track prokaryotic and eukaryotic carbon uptake along a meridional transect (Long. 52°W) in the North Atlantic to assess if ¹³C-resource partitioning between bacteria and archaea and ¹³C-labeled eukaryotic predators could be detected. One-liter SIP microcosms were amended with ¹³C-acetate or ¹³C-urea and incubated for 48 h. Our data indicated archaea often outcompeted bacteria for ¹³C-urea while both archaea and bacteria could incorporate ¹³C-acetate. This ¹³C label could also be tracked into eukaryotic microbes. The largest number of ¹³C-labeled eukaryotic OTUs, and the greatest percentage of …

Bridging Disciplines To Advance Elasmobranch Conservation: Applications Of Physiological Ecology, K Lyons, Js Bigman, Et Al, Kevin C. Weng, Et Al, Richard Brill, Cn Bedore

VIMS Articles

A strength of physiological ecology is its incorporation of aspects of both species' ecology and physiology; this holistic approach is needed to address current and future anthropogenic stressors affecting elasmobranch fishes that range from overexploitation to the effects of climate change. For example, physiology is one of several key determinants of an organism's ecological niche (along with evolutionary constraints and ecological interactions). The fundamental role of physiology in niche determination led to the development of the field of physiological ecology. This approach considers physiological mechanisms in the context of the environment to understand mechanistic variations that beget ecological trends. Physiological …

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 …

Massive Upland To Wetland Conversion Compensated For Historical Marsh Loss In Chesapeake Bay, Usa, Nathalie W. Schieder, David C. Walters, Matthew L. Kirwan

VIMS Articles

Sea level rise leads to coastal transgression, and the survival of ecosystems depends on their ability to migrate inland faster than they erode and submerge. We compared marsh extent between nineteenth-century maps and modern aerial photographs across the Chesapeake Bay, the largest estuary in North America, and found that Chesapeake marshes have maintained their spatial extent despite relative sea level rise rates that are among the fastest in the world. In the mapped region (i.e., 25% of modern Chesapeake Bay marshland),94 km2of marsh was lost primarily to shoreline erosion,whereas 101 km2of marsh was created by upland drowning.Simple projections over the …

Reef Height Drives Threshold Dynamics Of Restored Oyster Reefs, Allison M. Colden, Robert J. Latour, Rom Lipcius

VIMS Articles

Nonlinear threshold responses to biotic or abiotic forcing may produce multiple population trajectories dependent upon initial conditions, which can reinforce population recovery or drive local ex - tinction, yet experimental tests of this phenomenon are lacking in marine ecosystems. In field experiments at 4 sites in 2 tributaries of lower Chesapeake Bay, we examined demographic responses (density and survival) of eastern oyster Crassostrea virginica populations to reef height and associated gradients in sediment deposition and habitat complexity. After 2 yr, oyster reefs exhibited diverging trajectories to ward either degradation or persistence, dependent upon initial reef height. Reefs higher than 0.3 …

Subgenome Dominance In An Interspecific Hybrid, Synthetic Allopolyploid, And A 140-Year-Old Naturally Established Neo-Allopolyploid Monkeyflower, Patrick P. Edger, Ronald Smith, Micheal R. Mckain, (...), Gregory D. Conradi Smith, Joshua R. Puzey

Arts & Sciences Articles

Recent studies have shown that one of the parental subgenomes in ancient polyploids is generally more dominant, having retained more genes and being more highly expressed, a phenomenon termed subgenome dominance. The genomic features that determine how quickly and which subgenome dominates within a newly formed polyploid remain poorly understood. To investigate the rate of emergence of subgenome dominance, we examined gene expression, gene methylation, and transposable element (TE) methylation in a natural, <140-year-old allopolyploid (Mimulus peregrinus), a resynthesized interspecies triploid hybrid (M. robertsii), a resynthesized allopolyploid (M. peregrinus), and progenitor species (M. guttatus …

Beyond The Butcher's Block: The Animal Landscapes Of Eighteenth-Century Chesapeake And Lowcountry Plantations, Jenna Kay Carlson Dietmeier

Dissertations, Theses, and Masters Projects

This dissertation argues that working oxen, horses, and mules contributed to the physical and social landscapes of eighteenth-century plantations in the Chesapeake and the Lowcountry. This research embraces an animal landscape approach, exploring how humans and animals were both active agents in shaping animal husbandry strategies, social interactions, and power negotiations on plantations. This exploration utilized archaeological and historical sources, predominately faunal assemblages from Oxon Hill Manor, Maryland, Mount Vernon, Virginia, Drayton Hall, South Carolina, and Stobo Plantation, South Carolina; articulated equine skeletons from Jamestown Island, Virginia, and Yorktown, Virginia; and probate inventories from plantations within the eighteenth-century Upper Chesapeake …

Asynchrony Among Local Communities Stabilises Ecosystem Function Of Metacommunities, Kr Wilcox, At Tredennick, Se Koerner, E Grman, Lm Hallett, David S. Johnson, Et Al.

VIMS Articles

Temporal stability of ecosystem functioning increases the predictability and reliability of ecosystem services, and understanding the drivers of stability across spatial scales is important for land management and policy decisions. We used species-level abundance data from 62 plant communities across five continents to assess mechanisms of temporal stability across spatial scales. We assessed how asynchrony (i.e. different units responding dissimilarly through time) of species and local communities stabilised metacommunity ecosystem function. Asynchrony of species increased stability of local communities, and asynchrony among local communities enhanced metacommunity stability by a wide range of magnitudes (1-315%); this range was positively correlated with …

Abundance And Local-Scale Processes Contribute To Multi-Phyla Gradients In Global Marine Diversity, Gj Edgar, Tj Alexander, Js Lefcheck, Ae Bates, Sj Kininmonth, Et Al.

VIMS Articles

Among themost enduring ecological challenges is an integrated theory explaining the latitudinal biodiversity gradient, including discrepancies observed at different spatial scales. Analysis of Reef Life Survey data for 4127 marine species at 2406 coral and rocky sites worldwide confirms that the total ecoregion richness peaks in low latitudes, near +15 degrees N and -15 degrees S. However, although richness at survey sites is maximal near the equator for vertebrates, it peaks at high latitudes for large mobile invertebrates. Site richness for different groups is dependent on abundance, which is in turn correlated with temperature for fishes and nutrients for macroinvertebrates. …

A Synergistic Approach For Evaluating Climate Model Output For Ecological Applications, Rochelle Cavanaugh, Ej Murphy, Et Al, Walker O. Smith Jr., Et Al

VIMS Articles

Increasing concern about the impacts of climate change on ecosystems is prompting ecologists and ecosystem managers to seek reliable projections of physical drivers of change. The use of global climate models in ecology is growing, although drawing ecologically meaningful conclusions can be problematic. The expertise required to access and interpret output from climate and earth system models is hampering progress in utilizing them most effectively to determine the wider implications of climate change. To address this issue, we present a joint approach between climate scientists and ecologists that explores key challenges and opportunities for progress. As an exemplar, our focus …

Transmission Routes Maintaining A Viral Pathogen Of Steelhead Trout Within A Complex Multi-Host Assemblage, Rachel Breyta, Ilana Brito, Paige Ferguson, Gael Kurath, Kerry Naish, Maureen Purcell, Ar Wargo, Shannon Ladeau

VIMS Articles

This is the first comprehensive region wide, spatially explicit epidemiologic analysis of surveillance data of the aquatic viral pathogen infectious hematopoietic necrosis virus (IHNV) infecting native salmonid fish. The pathogen has been documented in the freshwater ecosystem of the Pacific Northwest of North America since the 1950s, and the current report describes the disease ecology of IHNV during 2000-2012. Prevalence of IHNV infection in monitored salmonid host cohorts ranged from 8% to 30%, with the highest levels observed in juvenile steelhead trout. The spatial distribution of all IHNV-infected cohorts was concentrated in two sub-regions of the study area, where historic …

Genetic Variation And Clonal Diversity In Introduced Populations Of Mimulus Guttatus Assessed By Genotyping At 62 Single Nucleotide Polymorphism Loci, Pauline O. Pantoja, Violeta I. Simon-Porcar, Joshua R. Puzey, Mario Vallejo-Marin

Arts & Sciences Articles

Background: Single nucleotide polymorphisms (SNPs) are increasingly being used to study non-native populations. SNPs are relatively information poor on a per locus basis, but allow genotyping more loci than others markers (e.g., microsatellites) and have the advantage of consistent allele calls between studies.Aims: We investigated the utility of a newly developed set of SNP markers, suitable for high throughput genotyping to characterise genotypic variation and population structure in non-native populations of the facultative clonal herb Mimulus guttatus in the United Kingdom (UK).Methods: We analysed 62 SNP markers and using a high throughput platform genotyped 383 individuals from 10 populations from …

Reconstructing Coastal Forest Retreat And Marsh Migration Response To Historical Sea Level Rise, Nathalie Schieder

Dissertations, Theses, and Masters Projects

Climate change assessments predict that rates of relative sea level rise will increase in the future, leading to enhanced inundation of low-lying coastal regions and a 20 – 50 % decline in salt marsh area by 2100. Global sea level rise began accelerating in the late 19th to early 20th century, and local rates along the U.S. mid-Atlantic coast are twice as fast as global estimates. Frequent flooding and salt stress associated with sea level rise lead to coastal transgression, and the survival of ecosystems depends on their ability to migrate inland faster than they erode and submerge. Here, I …

Fish Introductions And Light Modulate Food Web Fluxes In Tropical Streams: A Whole-Ecosystem Experimental Approach, Sarah M. Collins, Steven A. Thomas, Thomas Heatherly, Keeley L. Macneill, Antoine O. H. C. Leduc, Andres Lopez-Sepulcre, Bradley A. Lamphere, Rana W. El-Sabaawi, David N. Reznick, Catherine M. Pringle, Alexander S. Flecker

Arts & Sciences Articles

Decades of ecological study have demonstrated the importance of top-down and bottom-up controls on food webs, yet few studies within this context have quantified the magnitude of energy and material fluxes at the whole-ecosystem scale. We examined top-down and bottom-up effects on food web fluxes using a field experiment that manipulated the presence of a consumer, the Trinidadian guppy Poecilia reticulata, and the production of basal resources by thinning the riparian forest canopy to increase incident light. To gauge the effects of these reach-scale manipulations on food web fluxes, we used a nitrogen (N-15) stable isotope tracer to compare basal …

Atlantic Coast And Inner Shelf, David E. Krantz, Carl H. Hobbs Iii, Geoffrey L. Wikel

VIMS Books and Book Chapters

The continental margin of Virginia, and of North America more broadly, is the physical transition from the high elevation of the continent to the low of the ocean basin. This transition was created as rifting pulled apart the ancient supercontinent Pangaea to create the Atlantic Ocean basin. Tectonic forces fractured and stretched the bedrock to create a stair-step ramp that subsequently would be mantled with sediment built up by erosion and transport off the continent.

The Coastal Plain and Continental Shelf of Virginia are contiguous and discrete physiographic provinces of the continental margin delimited by the present elevation of sea …

Beyond The Benchtop And The Benthos: Dataset Management Planning And Design For Time Series Of Ocean Carbonate Chemistry Associated With Durafet (R)-Based Ph Sensors, Emily B. Rivest, M O'Brien, L Kapsenberg, Cc Gotschalk, Ca Blanchette, U Hoshijima, Ge Hofmann

VIMS Articles

To better understand the impact of ocean acidification on marine ecosystems, an important ongoing research priority for marine scientists is to characterize present-day pH variability. Following recent technological advances, autonomous pH sensor deployments in shallow coastal marine environments have revealed that pH dynamics in coastal oceans are more variable in space and time than the discrete, open-ocean measurements that are used for ocean acidification projections. Data from these types of deployments will benefit the research community by facilitating the improved design of ocean acidification studies as well as the identification or evaluation of natural and human-influenced pH variability. Importantly, the …