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Investigating The Spatiotemporal Distribution Of A Tick-Borne Pathogen, Ehrlichia Chaffeensis, Dylan Simpson Aug 2018

Investigating The Spatiotemporal Distribution Of A Tick-Borne Pathogen, Ehrlichia Chaffeensis, Dylan Simpson

Dissertations, Theses, and Masters Projects

The incidence of tick-borne diseases is on the rise in the US and around the world, due in part to emerging pathogens. However, the environmental drivers affecting these pathogens remain unclear. Most research on the topic in the US has focused on Borrelia burgdorferi, which causes Lyme, but it is unknown if the same conditions that affect B. burgdorferi also affect other pathogens, which may be carried by other ticks or reservoirs. The answer will help determine generalizable principles in tick-borne pathogen ecology, if they exist, as well as better manage for tick-borne pathogen risk in areas at risk from ...


The Role Of Ecological Interactions In Saltmarsh Geomorphic Processes, Bethany Lynn Williams Apr 2018

The Role Of Ecological Interactions In Saltmarsh Geomorphic Processes, Bethany Lynn Williams

Dissertations, Theses, and Masters Projects

Accelerated sea-level rise poses a significant threat to coastal habitats. Salt marshes are critical coastal ecosystems, providing a host of services such as storm protection, food production, and carbon storage. Persistence of salt marshes in the face of rising sea levels relies, in part, on vertical accretion. Current ecogeomorphic models and empirical studies emphasize the importance of the positive relationship between plant production and vertical accretion via sediment trapping by stems aboveground and belowground organic matter production. Thus, changes in plant production influence salt marsh persistence with sea-level rise. However, studies and models of marsh accretion do not consider the ...


Carry-Over Effects In Complex Life Cycles: Linking Larval Food Supply With Juvenile Recruitment Success In Sea Stars, Emily Richardson Apr 2018

Carry-Over Effects In Complex Life Cycles: Linking Larval Food Supply With Juvenile Recruitment Success In Sea Stars, Emily Richardson

Dissertations, Theses, and Masters Projects

The supply of new individuals into a population is one of the most important factors impacting species distributions and ecological interactions within a community. For marine invertebrates with complex life cycles, the supply of new individuals into a population can be influenced by factors experienced throughout their life history—before, during, or after metamorphosis. In recent years, scientists have begun to take a more holistic approach to understanding marine population assemblages by considering links between early life stages. When experiences in the pre-metamorphic life stages impact post-metamorphic life stages, this is known as carry-over effects. Because carry-over effects impact fitness ...


Individual- And Population-Level Effects Of Temperature And Hypoxia On Two Demersal Fishes In Chesapeake Bay, Benjamin Marcek Jan 2018

Individual- And Population-Level Effects Of Temperature And Hypoxia On Two Demersal Fishes In Chesapeake Bay, Benjamin Marcek

Dissertations, Theses, and Masters Projects

Anthropogenically-induced climate change has resulted in increases in water temperature and the frequency and severity of hypoxic events in coastal areas worldwide. Temperature and hypoxia affect fishes' energetics which can, in turn, be reflected in changes in reproductive success and shifts in spatial distributions. in an effort to quantify these changes in Atlantic croaker (Micropogonias undulatus) and spot (Leiostomus xanthurus) in Chesapeake Bay. I: (1) estimated standard and maximum metabolic rates and hypoxia tolerances at five temperatures (10, 15, 20, 25 and 30°C) using intermittent-flow respirometry, (2) examined the effects of hypoxia exposure on metrics of reproductive potential and ...


Movements, Habitat Utilization, And Post-Release Survival Of Cobia (Rachycentron Canadum) That Summer In Virginia Waters Determined Using Pop-Up Satellite Archival Tags (Psats), Douglas Jensen Jan 2018

Movements, Habitat Utilization, And Post-Release Survival Of Cobia (Rachycentron Canadum) That Summer In Virginia Waters Determined Using Pop-Up Satellite Archival Tags (Psats), Douglas Jensen

Dissertations, Theses, and Masters Projects

Cobia (Rachycentron canadum) is a cosmopolitan marine fish inhabiting tropical, sub-tropical, and temperate marine and estuarine waters. Recent changes in U.S. cobia management have sparked controversy and highlighted limitations in our understanding of seasonal movement patterns and problems with estimating recreational harvests. Consecutive years (2015 and 2016) of estimated overharvests from the Atlantic Migratory Group stock triggered accountability measures to prevent overfishing by recreational anglers. My project employed pop-up satellite archival tags (PSATs) to study cobia movements, habitat utilization, and post-release survival. It was, therefore, designed to enhance knowledge of cobia biology and aid sustainable management. We deployed 36 ...


Predicting The Impact Of Sea Level Rise On The Distribution Of Phragmites Australis And Spartina Alterniflora And Changes In Community Compositions In Tidal Freshwater Marshes Of James City County, Va, Abbey Humphreys Jun 2017

Predicting The Impact Of Sea Level Rise On The Distribution Of Phragmites Australis And Spartina Alterniflora And Changes In Community Compositions In Tidal Freshwater Marshes Of James City County, Va, Abbey Humphreys

Dissertations, Theses, and Masters Projects

With ongoing sea level rise (SLR), tidal freshwater marshes (TFMs) eventually will be flooded with more brackish water. The impact of more water and salt on the plant community of TFMs, however, is unknown. With SLR, both the invasive reed Phragmites australis and the native salt marsh grass Spartina alterniflora could become dominant species in TFMs. I am looking at determining how increases in salinity and inundation caused by sea level rise will impact the relative distribution of Phragmites and Spartina in tidal freshwater marshes in Southeastern Virginia. Using GIS, I summarized past expansion patterns by mapping the current and ...


Juvenile Blue Crab (Callinectes Sapidus) Response To Altered Nursery Habitat, Megan Wood Jan 2017

Juvenile Blue Crab (Callinectes Sapidus) Response To Altered Nursery Habitat, Megan Wood

Dissertations, Theses, and Masters Projects

Habitats of Chesapeake Bay have been altered due to anthropogenic impacts and climate change. Due to these human disturbances, seagrasses have been extirpated from many areas in lower Chesapeake Bay and persisting beds face future losses as water temperatures continue to rise. Further loss of seagrass habitat will negatively impact juvenile blue crabs (Callinectes sapidus) that use seagrass beds as nursery grounds. Habitat degradation allows for more successful introductions of exotic species, and the communities formed from the mixing of native and exotic species are known as emerging ecosystems. Gracilaria vermiculophylla, an exotic macroalga, may be an emerging nursery habitat ...


Juvenile Blue Crab Survival In Nursery Habitats: Predator Identification And Predation Impacts In Chesapeake Bay, Amanda Marie Bromilow Jan 2017

Juvenile Blue Crab Survival In Nursery Habitats: Predator Identification And Predation Impacts In Chesapeake Bay, Amanda Marie Bromilow

Dissertations, Theses, and Masters Projects

Predator populations can have significant impacts on prey recruitment success and prey population dynamics through consumption. Young, inexperienced prey are often most vulnerable to predation due to their small size and limited evasion capabilities. to reduce the risk of predation, new recruits and young juveniles typically settle in structured nursery habitats, such as seagrass beds, which promote higher survival by acting as refuges from predators. Thus, successful recruitment to the adult portion of the population is often dependent on the availability of suitable nursery habitat. In this thesis, I used field tethering experiments and gut content analyses to assess the ...


Ecosystem Services Of Restored Oyster Reefs In A Chesapeake Bay Tributary: Abundance And Foraging Of Estuarine Fishes, Bruce William Pfirrmann Jan 2017

Ecosystem Services Of Restored Oyster Reefs In A Chesapeake Bay Tributary: Abundance And Foraging Of Estuarine Fishes, Bruce William Pfirrmann

Dissertations, Theses, and Masters Projects

Oyster reef restoration may enhance the production of ecologically or economically important fish species, an ecosystem service, by providing refuge and foraging habitat. Predicting the effects of oyster habitat restoration on fisheries production in Chesapeake Bay requires a better understanding of fish habitat use, trophic dynamics, and the processes leading to production on a habitat-scale. The objective of this thesis was to evaluate the influence of restored subtidal oyster reefs on the abundance and foraging patterns of mobile estuarine fishes. Specifically, I compared the 1) abundance, 2) stomach fullness, 3) diet composition, and 4) daily consumption rate of fishes collected ...


Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky Jan 2017

Impact Of The Parasitic Nematode Anguillicoloides Crassus On American Eels (Anguilla Rostrata) In Chesapeake Bay, Zoemma Taudel Warshafsky

Dissertations, Theses, and Masters Projects

American eels are infected by the introduced parasitic nematode, Anguillicoloides crassus, which can cause significant damage to their swimbladders. Despite the high prevalence and severe damage caused by A. crassus, the population level effects on American eels are not well understood. The prevalence and swimbladder damage in young glass eels and elvers are relatively unstudied, despite the potential for this parasite to cause tissue damage. Additionally, the effects of environmental, temporal, and spatial variables have been debated in previous studies without consensus. Also, the potential for eels to recover from infection and tissue damage has been speculated but not definitively ...


Nitrogen Isotope Fractionation And Toxin Production During The Uptake Of Micromolar Concentrations Of Nitrate, Ammonium, And Urea By A Marine Dinoflagellate, Christen Taylor Armstrong Jan 2017

Nitrogen Isotope Fractionation And Toxin Production During The Uptake Of Micromolar Concentrations Of Nitrate, Ammonium, And Urea By A Marine Dinoflagellate, Christen Taylor Armstrong

Dissertations, Theses, and Masters Projects

Despite an increased global interest in harmful algal bloom (HAB) species and eutrophication, the relationship between nutrient sources and changes in species composition or toxicity remains unclear. Stable isotopes are routinely used to identify and track nitrogen (N) sources to water bodies, as sources can be differentiated based on stable isotope values. While literature is available describing N fractionation by diatoms and coccolithophores, data are greatly lacking regarding isotope fractionation by dinoflagellates. Here we investigate the fractionation of nitrogen isotopes by saxitoxin-producing Alexandrium fundyense, to validate the use of the δ15N of particulate organic matter and identify the nitrogen source ...


Spatiotemporal Abundance Patterns And Ecological Drivers Of A Nearshore U.S. Atlantic Fish And Invertebrate Assemblage, Mark A. Stratton Jan 2017

Spatiotemporal Abundance Patterns And Ecological Drivers Of A Nearshore U.S. Atlantic Fish And Invertebrate Assemblage, Mark A. Stratton

Dissertations, Theses, and Masters Projects

Taking an ecosystem approach to fisheries requires the consideration of relevant ecological processes within research and assessment frameworks. Processes affecting ecosystem productivity can be categorized as biophysical (climate variability, primary production), exploitative (fishing), or trophodynamic (food web interactions). This dissertation incorporates these three governing processes to characterize spatiotemporal diversity and population abundance trends for multiple demersal fish and invertebrate species that inhabit the nearshore zone (15-30 ft. depth) along portions of the U.S. Atlantic east coast.

Two large marine ecosystems (LMEs) encompass the U.S. East coast – the Southeast and Northeast U.S. Continental Shelf LMEs. The level of ...


Integrating Empirical Data And Ocean Drift Models To Better Understand Sea Turtle Strandings In Virginia, Bianca Silva Santos Jan 2017

Integrating Empirical Data And Ocean Drift Models To Better Understand Sea Turtle Strandings In Virginia, Bianca Silva Santos

Dissertations, Theses, and Masters Projects

Hundreds of stranded turtles wash up deceased on Virginia’s coastline each year, yet the causes of most stranding events are poorly understood. In this thesis, a carcass drift model was developed for the Chesapeake Bay, Virginia, to predict likely locations of mortality from coastal sea turtle stranding records. First, field studies were carried out to better parameterize the drift characteristics of buoyant sea turtle carcasses, namely, probable oceanic drift times and the impact of direct wind forcing on carcass drift. Based on the duration that tethered, free-floating turtle carcasses were buoyant, we determined that oceanic drift duration of turtle ...


Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp Jan 2016

Influence Of Structural Complexity And Location On The Habitat Value Of Restored Oyster Reefs, Melissa Ann Karp

Dissertations, Theses, and Masters Projects

In the Chesapeake Bay, < 1% of the historic oyster population remains, and efforts have been increasing to restore oysters and the services they provide. Building reefs that successfully provide ecosystem services–especially habitat and foraging grounds–may require different restoration techniques than those previously used, and success may depend on reef morphology (complexity), location, and environmental conditions. Salinity and habitat complexity are two important factors that may interact to effect benthic communities and predator-prey interactions on restored reefs. The goals of this project were: (1) Characterize the benthic communities on restored oyster reefs in lower Chesapeake Bay, and (2) examine the effects of structural complexity and salinity on benthic communities and predator-prey interactions. A two-year field survey of restored reefs was carried out in four rivers in lower Chesapeake Bay to characterize faunal communities on restored reefs and to quantify the effect of reef complexity on faunal communities. A laboratory mesocosm experiment was conducted to examine the effect of reef complexity on predator foraging. In total, 61 macrofaunal species were identified among all samples, and restored reefs supported on average, 6,169 org/m2 and 67.88 g-AFDW/m2. There were significant differences in the community composition and diversity among the rivers, and salinity was the environmental factor that best explained the observed differences in species composition across the rivers. Salinity and rugosity (i.e., structural complexity) both positively affected diversity, while salinity negatively affected macrofaunal abundance and biomass. Oyster density and rugosity positively affected macrofaunal biomass, and oyster density positively affected mud crab, polychaete, and mussel densities. In the mesocosm experiment, predator foraging, measured by proportion and number of prey consumed, was significantly reduced in the presence of oyster shell structure. However, predators were able to consume more prey when prey density was increased, even in the presence of oyster shell structure. These results combine to enhance our understanding of the benefits of increased habitat complexity for both prey and predators on restored oyster reefs. Increasing complexity worked to increase the abundance, biomass, and diversity of organisms inhabiting restored reefs, and even though predator consumption was reduced in the presence of structure compared to non-structured habitat, predators were able to consume more prey individuals when prey density was increased. Therefore, increasing the structure of oyster reef habitat may benefit prey species by providing refuge habitat, and benefit predators by providing an increased abundance of available prey items.


Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak Jan 2016

Reproductive Altruism, Social Diversity And Host Association In Sponge-Dwelling Snapping Shrimps, Synalpheus, Tin Chi Solomon Chak

Dissertations, Theses, and Masters Projects

The diversity of animal social strategies has interested evolutionary biologists since the time of Darwin. Eusociality—the apex of animal sociality—traditionally characterized by cooperative offspring care, overlapping generations and reproductive division of labor, was until recently known only in insects and a few vertebrate species. The independent evolution of eusociality in shrimps in the genus Synalpheus offers a unique opportunity to test the generality of social evolution theories that are based mainly on insects and social vertebrates. The genus Synalpheus is particularly ideal for comparative analysis because their social organizations are highly diverse, yet they share very similar ecology ...


Alexandrium Monilatum In The Lower Chesapeake Bay: Sediment Cyst Distribution And Potential Health Impacts On Crassostrea Virginica, Sarah Pease Jan 2016

Alexandrium Monilatum In The Lower Chesapeake Bay: Sediment Cyst Distribution And Potential Health Impacts On Crassostrea Virginica, Sarah Pease

Dissertations, Theses, and Masters Projects

The toxin-producing harmful algal bloom (HAB) species Alexandrium monilatum has long been associated with finfish and shellfish mortalities in the Gulf of Mexico. In the summer of 2007, A. monilatum re-emerged as a bloom-forming species in the Chesapeake Bay. Over the last decade, late summer blooms of A. monilatum have been expanding in range in the lower Chesapeake Bay and have reached record-high densities, particularly in the lower York River. This dinoflagellate species overwinters in the sediments as a resting cyst, and upon excystment under suitable environmental conditions produces blooms the following summer. The research presented here includes the first ...


Modulation Of Watershed Nutrient Loads By Tidal Creek Ecosystems On The Virginia Eastern Shore, Britt Leighanne Dean Jan 2016

Modulation Of Watershed Nutrient Loads By Tidal Creek Ecosystems On The Virginia Eastern Shore, Britt Leighanne Dean

Dissertations, Theses, and Masters Projects

While deeper estuaries typically demonstrate predictable responses to increased nutrient loads, responses in shallow systems are more varied, due in part to the presence of multiple benthic autotrophs. Shallow systems are particularly vulnerable to increases in watershed nutrient loads due to their position at the interface between land and open water. The prevailing conceptual model of eutrophication for shallow systems currently describes a succession in the dominant autotroph from seagrass to macroalgae to phytoplankton, but this model does not include benthic microalgae, which can sequester nutrients in photic systems. The Virginia Eastern Shore is characterized by shallow lagoons connected to ...


Zooplankton Community Composition And Grazing In The Amazon River Plume And Western Tropical North Atlantic Ocean, Brandon J. Conroy Jan 2016

Zooplankton Community Composition And Grazing In The Amazon River Plume And Western Tropical North Atlantic Ocean, Brandon J. Conroy

Dissertations, Theses, and Masters Projects

Large river plumes and frontal zones are important physical features influencing plankton distribution in the marine environment. In the western tropical North Atlantic Ocean (WTNA) the Amazon River plume may extend over an area reaching 1.5 x 106 km2. The freshwater plume creates a low-density lens in the surface 25m and supplies silicon and phosphorus to the WTNA. These physical and chemical gradients create an ideal environment for large-scale blooms of diatom diazotroph associations (DDAs), a symbiotic relationship between nitrogen-fixing cyanobacteria and chain-forming diatoms. While the physical and chemical properties of the plume with regard to influences on phytoplankton ...


Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez Jan 2016

Assemblage Dynamics Of Larval Fishes In The York River Of Virginia And The Chesapeake Bay, Cindy Marlene Marin Martinez

Dissertations, Theses, and Masters Projects

This thesis developed from the VIMS Larval Fish Monitoring Program, which began in 2007 as part of a study comparing the larval fish assemblages of Chesapeake and Delaware Bays. Ribeiro et al. (2015) analyzed data from the first three years of this time series to describe the temporal variation in the larval fish assemblages. After this initial study was completed (three years in duration), the sampling continued at the fixed station near the mouth of the York River, which was used to represent the Chesapeake Bay. For this thesis, therefore, eight years of data (2007-2015) were available to investigate temporal ...


Modeling Phytoplankton Community Response To Nutrient Loading And Climate Change In A Shallow Temperate Estuary, Sara Aimee Blachman Jan 2016

Modeling Phytoplankton Community Response To Nutrient Loading And Climate Change In A Shallow Temperate Estuary, Sara Aimee Blachman

Dissertations, Theses, and Masters Projects

Phytoplankton account for at least half of all primary production in estuarine waters and are at the center of biogeochemical cycles and material budgets. Environmental managers use water column chlorophyll-a (chl-a) concentrations as a basic water quality indictor, as the problems of eutrophication and hypoxia are intrinsically linked to excessive phytoplankton growth. Evidence suggests that the distribution and frequency of harmful algal blooms may be increasing worldwide. For the most part, phytoplankton communities follow a standard seasonal pattern, with specific groups dominating the assemblage during the time of year when environmental conditions correspond to their requisites for growth. However, climate ...


Habitat Use Of The Declining Wood Thrush In Coastal Virginia, Vitek Jirinec Jan 2015

Habitat Use Of The Declining Wood Thrush In Coastal Virginia, Vitek Jirinec

Dissertations, Theses, and Masters Projects

No abstract provided.


Spatial Modeling Of A Realized Niche: Investigating The Invasion Of Sweet Fennel (Foeniculum Vulgare Mill) Into Coastal Habitats Of Virginia's Eastern Shore, Kathryn Elizabeth Maccormick Jan 2015

Spatial Modeling Of A Realized Niche: Investigating The Invasion Of Sweet Fennel (Foeniculum Vulgare Mill) Into Coastal Habitats Of Virginia's Eastern Shore, Kathryn Elizabeth Maccormick

Dissertations, Theses, and Masters Projects

No abstract provided.


Phylogeny, Ontogeny And Distribution Of The Ribbonfishes (Lampridiformes: Trachipteridae), Jennifer M. Martin Jan 2015

Phylogeny, Ontogeny And Distribution Of The Ribbonfishes (Lampridiformes: Trachipteridae), Jennifer M. Martin

Dissertations, Theses, and Masters Projects

The ribbonfish family Trachipteridae (Lampridiformes) includes three well-defined genera (Trachipterus, Desmodema, and Zu), which are distributed worldwide throughout the pelagic marine environment as with most families of Lampridiformes, drastic changes in morphology occur throughout ontogeny due to extreme allometric growth. Combined with the rarity of specimens, this has led to the description of different life history stages as different species, rather than as part of the ontogenetic continuum of a single species. There is significant uncertainty concerning the ontogeny, distribution, nomenclature, number and phylogenetic affinity of trachipterid and other lampridiform genera.;The first chapter of my dissertation is a taxonomic ...


Using Human Footprint Models And Land-Cover Variability To Predict Ecological Processes, Jessica Anne Pouder Jan 2014

Using Human Footprint Models And Land-Cover Variability To Predict Ecological Processes, Jessica Anne Pouder

Dissertations, Theses, and Masters Projects

No abstract provided.


Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister Jan 2014

Structure, Drivers, And Trophic Interactions Of The Demersal Fish Community In Chesapeake Bay, Andre Buchheister

Dissertations, Theses, and Masters Projects

Management of fisheries resources is increasingly broadening its scope from single-species approaches to more holistic, ecosystem-based approaches that account for interactions of fish with a variety of ecological factors, such as predators, prey, and habitat. This ecosystem based fisheries management (EBFM) approach requires thorough biological and ecological understanding of systems pertaining to community structure, habitat suitability, and food web interactions. to strengthen the ecological underpinnings of EBFM efforts in Chesapeake Bay, the largest estuary in the USA, I conducted synoptic analyses examining the structure, function, and patterns of the bay's demersal fish community. This research relied on I0 years ...


Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney Jan 2014

Impact Of Mercury Exposure On Birds And The Effect Of Molt On Mercury Depuration In Songbirds, Margaret Crossley Whitney

Dissertations, Theses, and Masters Projects

No abstract provided.


Using A Multi-Scale Life-History Approach To Explore Occupancy Patterns Of Pond-Breeding Anurans In Eastern Virginia, Daniel Stewart Ramos Jan 2013

Using A Multi-Scale Life-History Approach To Explore Occupancy Patterns Of Pond-Breeding Anurans In Eastern Virginia, Daniel Stewart Ramos

Dissertations, Theses, and Masters Projects

No abstract provided.


Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel Jan 2013

Abundance, Structure And Function Of Zooplankton-Associated Bacterial Communities Within The York River, Va, Samantha L. Bickel

Dissertations, Theses, and Masters Projects

Mesozooplankton function as microbial microhabitats and can support concentrations of bacteria orders of magnitude higher than in the surrounding water. These zooplankton-associated bacteria can have much higher production rates than their free-living counterparts. Portions of the zooplankton microhabitat may also be anoxic and provide refuge for anaerobic bacteria and their associated processes within the oxygenated water column. Despite their common presence in the marine environment, zooplankton-associated bacteria are largely ignored by microbial ecologists and zooplankton ecologists alike. Consequently, factors which influence zooplanktonassociated bacterial abundance, community composition and function, and how zooplankton-associated bacteria compare to free-living bacteria are not well known ...


Modeling The Formation Of Periodic Hypoxia In Partially Mixed Estuaries And Its Response To Oligotrophication And Climate Change, Samuel J. Lake Jan 2013

Modeling The Formation Of Periodic Hypoxia In Partially Mixed Estuaries And Its Response To Oligotrophication And Climate Change, Samuel J. Lake

Dissertations, Theses, and Masters Projects

The development of hypoxia represents one of the most common and ecologically detrimental effects of anthropogenic nutrient enrichment in coastal marine ecosystems. Due to the physiological importance of oxygen as a key component of metabolic processes, the development and persistence of hypoxia can reduce the distribution of important species, modify food webs, decrease diversity and richness, and sub-lethally affect growth and reproductive rates. While many recent studies have focused on the global increase in hypoxia and highlighted the need for nutrient reduction strategies, some key processes associated with hypoxia remain understudied. of particular importance is the resolution of the major ...


Habitat And Fish Population Dynamics: Advancing Stock Assessments Of Highly Migratory Species, Patrick D. Lynch Jan 2013

Habitat And Fish Population Dynamics: Advancing Stock Assessments Of Highly Migratory Species, Patrick D. Lynch

Dissertations, Theses, and Masters Projects

Fisheries sustainability is inherently linked to an understanding of the population-level effects of fishing. With an accurate characterization of historical fish and fishery dynamics, management agencies are more equipped to create regulations that sustain fishery resources over the long term. The overarching goal of this dissertation is to contribute to the advancement of fisheries stock assessment and promote resource sustainability. My research focused on highly migratory species (HMS), particularly fishes that reside in the open ocean. These species constitute some of the highest valued global fisheries; however, numerous factors compromise HMS stock assessment and management. These challenges are fully described ...