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Full-Text Articles in Physical Sciences and Mathematics

Ecological And Economic Effects Of Derelict Fishing Gear In The Chesapeake Bay 2015/2016 Final Assessment Report, Donna M. Bilkovic, H. Ward Slacum Jr., Kirk J. Havens, Danielle Zaveta, Christopher F.G. Jeffrey, Andrew M. Scheld, David Stanhope, Kory Angstadt, John D. Evans Oct 2016

Ecological And Economic Effects Of Derelict Fishing Gear In The Chesapeake Bay 2015/2016 Final Assessment Report, Donna M. Bilkovic, H. Ward Slacum Jr., Kirk J. Havens, Danielle Zaveta, Christopher F.G. Jeffrey, Andrew M. Scheld, David Stanhope, Kory Angstadt, John D. Evans

Reports

Derelict fishing gear represents a major challenge to marine resource management: whether through deliberate abandonment or through accidental loss, derelict traps in particular have significant negative effects both economic (e.g., reduced fishery harvest from ghost fishing and gear competition that leads to the reduced efficiency of active gear) and ecological (e.g., degraded habitats and marine food webs and crab and bycatch mortality). Throughout the Chesapeake Bay, commercial harvest of hard-shelled blue crabs is a major fishing activity: every year sees the deployment of several hundred thousand blue crab traps (known locally as crab “pots”) across the Bay, of which an …


Assessing Ecological And Economic Effects Of Derelict Fishing Gear: A Guiding Framework, Christopher F.G. Jeffrey, Kirk J. Havens, H. Ward Slacum Jr., Donna Marie Bilkovic, Danielle Zaveta, Andrew M. Scheld, Sean Willard, John D. Evans Oct 2016

Assessing Ecological And Economic Effects Of Derelict Fishing Gear: A Guiding Framework, Christopher F.G. Jeffrey, Kirk J. Havens, H. Ward Slacum Jr., Donna Marie Bilkovic, Danielle Zaveta, Andrew M. Scheld, Sean Willard, John D. Evans

Reports

Developing standardized protocols to assess the ecological and socio-economic effects of marine debris – especially, derelict fishing gear – is critical for the protection of natural resources and for evaluating policies and programs designed to reduce and remove debris. This document outlines a Derelict Fishing Gear Assessment Framework to guide the development and implementation of derelict gear assessment, management and mitigation. The framework draws from techniques and protocols developed to assess derelict crab traps effects in the Chesapeake Bay and on past derelict gear assessments either conducted by or known to the framework authors. However, this framework is generalized and …


Integrated Assessment Of Oyster Reef Ecosystem Services: Macrofauna Utilization Of Restored Oyster Reefs, M. Lisa Kellogg, Kennedy T. Paynter, Paige G. Ross, Jennifer C. Dreyer, Cate Turner, Manisha Pant, Alan Birch, Edward Smith May 2016

Integrated Assessment Of Oyster Reef Ecosystem Services: Macrofauna Utilization Of Restored Oyster Reefs, M. Lisa Kellogg, Kennedy T. Paynter, Paige G. Ross, Jennifer C. Dreyer, Cate Turner, Manisha Pant, Alan Birch, Edward Smith

Reports

Within the Harris Creek Oyster Sanctuary in the Maryland portion of Chesapeake Bay, we evaluated relationships between basic oyster reef characteristics and the abundance and biomass of macrofauna. The eight sites selected for these studies included five restored oyster reef sites and three sites suitable for restoration that had not been restored. These sites encompassed a range of oyster biomass density and were spread throughout the sanctuary area. At each site one month prior to each of four sampling periods, divers filled four wire mesh baskets (0.1m2 surface area x 15 cm depth) with material from the site and embedded …


Virginia Game Fish Tagging Program Annual Report 2015, Susanna Musick, Lewis Gillingham May 2016

Virginia Game Fish Tagging Program Annual Report 2015, Susanna Musick, Lewis Gillingham

Reports

Through 2015, the Virginia Game Fish Tagging Program has maintained a 20-year database of records for tagged and recaptured fish. The program is a cooperative project of the Virginia Saltwater Fishing Tournament (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 Relative Abundance Of American Shad And River Herring In Virginia Rivers 2015 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee Apr 2016

Monitoring Relative Abundance Of American Shad And River Herring In Virginia Rivers 2015 Annual Report, Eric J. Hilton, Robert Latour, Patrick E. Mcgrath, Brian Watkins, Ashleigh Magee

Reports

Concern about the decline in landings of American shad (Alosa sapidissima) along the Atlantic coast prompted the development of an interstate fisheries management plan (FMP) under the auspices of the Atlantic States Marine Fisheries Management Program (ASMFC 1999). Legislation enables imposition of federal sanctions on fishing in those states that fail to comply with the FMP. To be in compliance, coastal states are required to implement and maintain fishery-dependent and fishery-independent monitoring programs as specified by the FMP. For Virginia, these requirements include spawning stock assessments, the collection of biological data on the spawning run (e.g., age-structure, sex ratio, and …


Integrated Assessment Of Oyster Reef Ecosystem Services: Fish And Crustacean Utilization And Trophic Linkages, M. Lisa Kellogg, Paige G. Ross, Mark Luckenbach, Jennifer C. Dreyer, Manisha Pant, Alan Birch, Sean Fate, Edward Smith, Kennedy Paynter Mar 2016

Integrated Assessment Of Oyster Reef Ecosystem Services: Fish And Crustacean Utilization And Trophic Linkages, M. Lisa Kellogg, Paige G. Ross, Mark Luckenbach, Jennifer C. Dreyer, Manisha Pant, Alan Birch, Sean Fate, Edward Smith, Kennedy Paynter

Reports

Using a regression design that encompassed the continuum of oyster reef biomass density in Harris Creek, MD, from unrestored reefs to those restored reefs with the greatest oyster biomass, we examined finfish and crustacean utilization of these habitats. Of the eight sites studied, three had not been subject to any restoration activities and five had been planted in 2012 with juvenile oysters set on oyster shell. All sites were sampled in April, June, August, and October 2015. During each sampling period, we assessed abundance, total length and biomass of finfish and examined gut contents to assess the diets of selected …


Virginia Shellfish Aquaculture Situation And Outlook Report : Results Of The 2015 Virginia Shellfish Aquaculture Crop Reporting Survey, Karen Hudson, Thomas J. Murrary Mar 2016

Virginia Shellfish Aquaculture Situation And Outlook Report : Results Of The 2015 Virginia Shellfish Aquaculture Crop Reporting Survey, Karen Hudson, Thomas J. Murrary

Reports

The hatchery-based shellfish aquaculture industry in Virginia continues to grow adding significant value to the Commonwealth’s seafood marketplace. Today, watermen harvest both hard clams and oysters from the Commonwealth’s public resources, albeit at rates diminished from historic levels. At the same time, Virginia’s watermen-farmers, utilizing production from a land-based hatchery, are providing additional quantities of quality shellfish to consumers. This survey, in its 10th year, is intended to continue annual assessments with which to gauge growth and inputs in Virginia’s hatchery-based shellfish aquaculture industry. This report is based upon an industry survey completed during the first quarter of 2016. While …


The Dilemma Of Derelict Gear: Datasets, Andrew M. Scheld, Donna M. Bilkovic, Kirk J. Havens Jan 2016

The Dilemma Of Derelict Gear: Datasets, Andrew M. Scheld, Donna M. Bilkovic, Kirk J. Havens

Data

No abstract provided.


Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2016), Troy D. Tuckey, Mary C. Fabrizio Jan 2016

Evaluating Recruitment Of American Eel, Anguilla Rostrata, In The Potomac River (Spring 2016), 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. Landings from Chesapeake Bay typically represent 60% of the annual United States commercial harvest (ASMFC 2012). American Eel is also important to the recreational fishery as it is often used live as bait for Striped Bass (Morone saxatilis) and Cobia (Rachycentron canadum). In 2012, Chesapeake Bay commercial landings of American Eel (771,536 lbs) were 72% of the U.S. landings (personal communication from the National Marine Fisheries Service, Fisheries Statistics Division). Since the 1980s, harvest along the U.S. Atlantic Coast …


The Status Of Virginia's Public Oyster Resource 2015, Melissa Southworth, Roger L. Mann Jan 2016

The Status Of Virginia's Public Oyster Resource 2015, Melissa Southworth, Roger L. Mann

Reports

This report summarizes data collected during 2015 in the Virginia portion of the Chesapeake Bay. The report is composed of two parts, part one, oyster recruitment (shell string) in Virginia and part two, dredge survey of selected oyster bars in Virginia.


Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien Jan 2016

Influence Of Perkinsus Marinus Infection And Oyster Health On Levels Of Human-Pathogenic Vibrios In Oysters, Lydia M. Bienlien

Dissertations, Theses, and Masters Projects

The eastern oyster Crassostrea virginica is an ecologically and commercially important species whose natural populations have been devastated by overharvesting, habitat destruction, and disease, but the rapid growth of oyster aquaculture has shown potential to restore the economic significance of this species. A key threat to the growth and sustainability of oyster aquaculture is the association of human-pathogenic Vibrio bacteria with product marketed for raw consumption. Two Vibrio species, Vibrio vulnificus and Vibrio parahaemolyticus, are the causes of the highest rates of seafood consumption-related mortality and gastrointestinal illness, respectively. Identification of the factors influencing V. vulnificus and V. parahaemolyticus prevalence …


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.


The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje Jan 2016

The Effects Of Drifting Fish Aggregating Devices On Bycatch In The Tropical Tuna Purse Seine Fisheries In The Atlantic And Indian Oceans, Julia Snouck-Hurgronje

Dissertations, Theses, and Masters Projects

Thousands of floating objects, known as drifting fish aggregating devices (dFADs), are released every year by commercial tropical tuna purse seine vessels in the three equatorial oceans to aggregate tuna and increase catch. The escalation in the number of dFADs deployed over the last three decades has caused changes in fishing effort that are poorly reflected in traditional indices of purse seine effort and catch per unit of effort (CPUE). In addition, concerns have been raised regarding the impacts of such high numbers of dFADs being deployed on both catch and bycatch species. I studied two aspects of dFAD deployments …