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Full-Text Articles in Animal Sciences
Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace
Habitat Utilization And Salinity Tolerance Of The Sandbar Shark, Carcharhinus Plumbeus, In Virginia, Leonard Pace
Dissertations, Theses, and Masters Projects
No abstract provided.
Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield
Sources Of Mortality, Movements And Behavior Of Sea Turtles In Virginia, Katherine Lamont. Mansfield
Dissertations, Theses, and Masters Projects
Aerial surveys are commonly used to evaluate in-water sea turtle abundances. A correction is applied to account for turtles diving below the observed surface. Historically, observations of summer/fall surfacing behavior were used for this correction, assuming constant behavior among seasons. Using radio/acoustic telemetry, seasonal differences in sea turtle surfacing behavior were determined among Kemp's ridleys and loggerheads. Mean time spent at surface in the spring ranged between 9.9%-30.0% with significant differences among individuals. Observed surfacing times were higher than historic summer/fall observations (Byles 1988; 5.3%), indicating that historic springtime abundances were overestimated by 50%-80%. Aerial surveys (2001-2004) indicated a 65%-75% …
Size-Selectivity Of The Commercial Sea Scallop (Placopecten Magellanicus) Dredge: Evaluation The Performance Of The New Bedford Style Dredge Configured With 4-Inch Rings And A 10-Inch Twine Top Using The Select Model, Noelle Yochum
Dissertations, Theses, and Masters Projects
A size-selectivity curve was constructed to characterize the performance of the New Bedford style Atlantic sea scallop (Placopecten magellanicus) dredge when it is configured to meet the requirements of Amendment #10 to the Sea Scallop Fishery Management Plan. The curve was generated using the SELECT model on catch-at-length data, obtained by simultaneously towing a New Bedford style dredge and a non-selective National Marine Fisheries Service sea scallop survey dredge from commercial scallop vessels. Data were collected during three cruises in the Northwest Atlantic between 2005 and 2006. One cruise was completed in Georges Bank (Groundfish Closed Area II) and two …
Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha
Ecology And Conservation Of Virginia Shark Species: Analysis Of Thirty Years Of Virginia Long-Line Shark Census Data, 1974--2004, Daniel Stuart Ha
Dissertations, Theses, and Masters Projects
Sharks of the Atlantic coast of the United States have suffered increased fishing pressure in last three decades. Commercial and recreational catches jumped in the mid to late 1980's, leading to regulation by the National Marine Fisheries Service in the early 1990's. The Virginia Institute of Marine Sciences' shark long-line survey, begun in 1974, and continuing to the present day, is thus well positioned to look at the effects of this fishing mortality on sharks. Using GAM modelling, six of ten shark species analyzed, including the most common species, Carcharhinus plumbeus, suffered declines of from 98-99% of early abundances in …
Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins
Migratory And Spawning Behavior Of American Shad In The James River, Virginia, Aaron W. Aunins
Dissertations, Theses, and Masters Projects
No abstract provided.
Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman
Diel And Site-Specific Feeding Of Young Striped Bass In A Heterogeneous Nursery Habitat, Sarah C. Muffelman
Dissertations, Theses, and Masters Projects
The Chesapeake Bay spawning stock of striped bass, Morone saxatilis, is considered one of the largest sources of juvenile production along the Atlantic coast and exhibits a high degree of interannual recruitment variability. Year class strength is judged by near-shore seine surveys that cover major tributaries of Chesapeake Bay and survey results are incorporated into annual stock assessments. In these surveys, the contribution of the Rappahannock River (Virginia) to total production is significant. In this system, abundance of juveniles is highest at a single seine site, suggesting that juvenile production may be related to habitat heterogeneity and food availability. To …
Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke
Developing A Stock Assessment For The Barndoor Skate (Dipturus Laevis) In The Northeast United States, Todd Gedamke
Dissertations, Theses, and Masters Projects
The barndoor skate Dipturus laevis is one of seven species in the United States Northwest Atlantic skate complex. The species received little attention until a recent article published in Science reported that the barndoor skate might be on the brink of extinction. In this study, we address not only the virtual lack of information on the life history of the species, but also develop methodologies to assist in the assessment of the barndoor skate population. to investigate the life history of the species, data were collected from 2,310 specimens caught during commercial sea scallop dredging in the southern section of …
Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston
Role Of Apolipoprotein A-1 In Defense Against Bacteria By Striped Bass (Morone Saxatilis), L. Danielle Johnston
Dissertations, Theses, and Masters Projects
No abstract provided.
Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde
Development Of Generalized Index-Removal Models, With Particular Attention To Catchability Issues, Thomas F. Ihde
Dissertations, Theses, and Masters Projects
The index-removal method estimates abundance, exploitation and catchability coefficient, given surveys conducted before and after a known removal. The method assumes a closed population between surveys. Index-removal has seldom been applied due to its strong assumption of constant survey catchabilities. This work generalizes the method to allow multiple years of data to be incorporated, and the assumptions of the original model to be relaxed. If catchability is constant across years, precision can be improved by analyzing multi-year data simultaneously. Two multiple-year models were developed: the first, 1qIR, assumes constant catchability within and among years; the second, 2qIR, allows catchability to …