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Accounting For Undesirable Outputs In Productivity Measurements: Application To The California-Oregon Drift Gillnet Fishery, Tara L. Scott
Accounting For Undesirable Outputs In Productivity Measurements: Application To The California-Oregon Drift Gillnet Fishery, Tara L. Scott
Dissertations, Theses, and Masters Projects
Many production activities typically produce undesirable outputs, e.g., the production of the pollutant sulfur dioxide in the generation of electricity. Traditional economic metrics may overstate the efficiency and productivity of these production activities by failing to account for the undesirable outputs. These omissions can lead to conclusions that are biased against resource conservation and protection. Many fisheries capture their target species concomitantly with undesirable outputs such as bycatch of juvenile fish, marine mammals, sea birds, and sea turtles. One such fishery is the California-Oregon (CA/OR) drift gillnet fishery (DGNF), which incidentally takes protected species, such as sea turtles and marine …
Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor
Bioavailability Of Biosolids- And Consumer Product-Associated Polybrominated Diphenyl Ether (Pbde) Flame Retardants To Terrestrial Invertebrates, Michael O. Gaylor
Dissertations, Theses, and Masters Projects
The primary objectives of this research were therefore to evaluate polybrominated diphenyl ether (PBDE) bioavailability to ecologically distinct soil invertebrates exposed to Penta-BDE-treated consumer polyurethane foam (PUF) products and biosolid products with incurred PBDEs. In laboratory bioassays, earthworms (Eisenia fetida) bioaccumulated SigmaPBDEs (47+99+100+183) up to 11,000 mug/kg lipid after 28 days from a mixture of artificial soil and anaerobically-digested sludge biosolid (ADB). Earthworms also bioaccumulated SigmaPBDEs (47+99+100+153+154+183) up to 13,500 and 838,000 mug/kg lipid after 28 d from a mixture of artificial soil and composted sludge biosolid (CB) and Penta-BDE-spiked artificial soil (SAS), respectively. No previous lab studies on bioaccumulation …
Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz
Persistent Organic Pollutants(Pops) As Tracers Of Environmental Change And Antarctic Seabird Ecology, Heidi N. C. Geisz
Dissertations, Theses, and Masters Projects
Antarctic seabirds including Adelie penguins (Pygoscelis adeliae), south polar skuas (Catharacta maccormicki), southern giant petrels (Macronectes gigantus) are high trophic level predators that accumulate persistent organic pollutants (POPs) present in the food webs in which they forage. Little is known about the levels of POPs in some Antarctic organisms (e.g. southern giant petrels), as well as the long-term trends of POPs in the Antarctic ecosystem. Samples from all three seabird species were collected post mortem, including eggs, from the Western Antarctic Peninsula (WAP) and in the Ross Sea throughout the austral summer breeding seasons of 2004--2006. The samples were analyzed …
Incorporating Industry Based Dredge Surveys Into The Assessment Of Sea Scallops, Placopecten Magellanicus, David B. Rudders
Incorporating Industry Based Dredge Surveys Into The Assessment Of Sea Scallops, Placopecten Magellanicus, David B. Rudders
Dissertations, Theses, and Masters Projects
Cooperative research utilizing industry vessels represents a viable approach to acquire the data necessary to meet the increasing needs associated with the modern management of marine resources. This dissertation addresses a variety of topics associated with the integration of commercial vessels into the stock assessment of the sea scallop, Placopecten magellanicus. In this study we evaluate the efficacy of utilizing industry vessels with respect to topics that range from rotational closed area survey design, sampling gear evaluation as well as an experiment that broadens the scale of the traditional use of industry vessels in this fishery and provides data to …
Assessing The Functional Status Of Created Wetlands In Eastern Virginia Via A Soil And Vegetative Developmental Trajectory, Sara Elizabeth Kreisel
Assessing The Functional Status Of Created Wetlands In Eastern Virginia Via A Soil And Vegetative Developmental Trajectory, Sara Elizabeth Kreisel
Dissertations, Theses, and Masters Projects
No abstract provided.
The Lateral Extent And Spatial Variation Of Mercury Exposure In Birds And Their Prey Near A Polluted River, Mikaela Gioia Selene Howie
The Lateral Extent And Spatial Variation Of Mercury Exposure In Birds And Their Prey Near A Polluted River, Mikaela Gioia Selene Howie
Dissertations, Theses, and Masters Projects
No abstract provided.
Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett
Effects Of Habitat Quality On Secondary Production In Shallow Estuarine Waters And The Consequences For The Benthic-Pelagic Food Web, David James Gillett
Dissertations, Theses, and Masters Projects
Anthropogenic degradation of coastal and estuarine habitats is an ongoing problem facing scientists, natural resource mangers, and the general public. Decreases in habitat quality produce relatively predictable changes in the structure and composition of macrobenthic communities and it has traditionally been assumed that the ecosystem functions of the community change as well. In Chesapeake Bay, the most pervasive cause for the degradation of benthic habitats is the excessive inputs of nutrients that lead to eutrophication and the accumulation of organic matter in the system. Working within this framework, a study was conducted investigating changes in macrobenthic (i.e., secondary) production along …
Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke
Alternative Substrates As A Native Oyster (Crassostrea Virginica) Reef Restoration Strategy In Chesapeake Bay, Russell Paul Burke
Dissertations, Theses, and Masters Projects
Oyster shell for native oyster reef restoration is scarce in Chesapeake Bay and other estuaries (Chapter 1). Consequently, alternative substrates merit consideration in oyster restoration. This dissertation examines the suitability of shell alternatives, including granite, concrete, limestone marl, concrete modules and reefballs with reef surveys and experiments in the Rappahannock and Lynnhaven Rivers of Chesapeake Bay. Oyster recruitment, growth, survival, density, biomass, condition, and disease stress, as well as reef accretion and persistence, were measured. In the Lynnhaven River, intertidal riprap had a mean density of 978 oysters m-2 (165 g AFDM m-2) and peak densities > 2000 oysters m-2 (Chapter …
Spatial And Temporal Patterns In Erosional And Depositional Processes: Physical And Biological Controls In The York River, Chesapeake Bay, Virginia, Cielomar Rodríguez-Calderon
Spatial And Temporal Patterns In Erosional And Depositional Processes: Physical And Biological Controls In The York River, Chesapeake Bay, Virginia, Cielomar Rodríguez-Calderon
Dissertations, Theses, and Masters Projects
No abstract provided.
Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson
Survival In An Urbanized Landscape: Radio-Tracking Fledgling Eastern Bluebirds (Sialia Sialis) On Golf Courses, Allyson Kathleen Jackson
Dissertations, Theses, and Masters Projects
No abstract provided.
Acoustics Of Anthropogenic Habitats: The Impact Of Noise Pollution On Eastern Bluebirds, Caitlin Rebecca Kight
Acoustics Of Anthropogenic Habitats: The Impact Of Noise Pollution On Eastern Bluebirds, Caitlin Rebecca Kight
Dissertations, Theses, and Masters Projects
An increasing number of habitats are affected by anthropogenic noise pollution, which is often louder, has a different frequency emphasis, and may occur over a different temporal scale, than natural noise. An increasing number of studies indicate that acoustically-communicating animals in such areas can modify their vocalizations in order to make themselves heard over the noise, but many questions still remain, including: How taxonomically widespread is vocal flexibility in response to anthropogenic noise, and do all vocally flexible species employ the same mechanisms to escape acoustic masking? Are there fitness repercussions for living, communicating, and breeding in noisy habitats? and, …
Copepod Carcasses, Mortality And Population Dynamics In The Tributaries Of The Lower Chesapeake Bay, David Thomas. Elliott
Copepod Carcasses, Mortality And Population Dynamics In The Tributaries Of The Lower Chesapeake Bay, David Thomas. Elliott
Dissertations, Theses, and Masters Projects
Several studies have documented the occurrence of substantial numbers of zooplankton carcasses in marine field samples. However, the potential effect of carcasses on conclusions resting on zooplankton abundance estimates, and the reasons for carcass occurrence have been largely disregarded. Many field studies do not account for the presence of carcasses in their sampling methodology. Zooplankton carcasses in situ are significant for several reasons. as concentrated particles of organic matter in the water column, zooplankton carcasses can be important vehicles for organic matter transport and hotspots of microbial abundance and activity. If dead animals are treated alive, carcasses could bias the …