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Full-Text Articles in Life Sciences
Status, Distribution And Reproductive Rates Of American Oystercatchers In Virginia, Alexandra Lee Wilke
Status, Distribution And Reproductive Rates Of American Oystercatchers In Virginia, Alexandra Lee Wilke
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 …
Application Of Survival Analysis Methods To Pulsed Exposures: Exposure Duration, Latent Mortality, Recovery Time, And The Underlying Theory Of Survival Distribution Models, Yuan Zhao
Dissertations, Theses, and Masters Projects
Ecotoxicologists adopted median lethal concentration (LC50) methods from mammalian toxicology. This conventional LC50 approach has shortcomings. Fixing the exposure duration and selecting the 50% mortality level result in loss of ecologically relevant information generated at all other times. It also ignores latent mortality that can manifest after exposure ends. as a result, it cannot adequately predict pulsed exposure effects in which concentration, duration, and frequency of pulses change through time. The underlying theory of the dose-response models used to calculate LC50 values, stochastic versus individual effective dose (IED) theory, has not been tested rigorously either. In this study, the effects …
Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston
Stock Enhancement Of Caribbean Spiny Lobster, Panulirus Argus Latrielle, Using Artificial Shelters: Patterns Of Survival And Dynamics Of Shelter Selection, David Bryan Eggleston
Dissertations, Theses, and Masters Projects
Field tethering experiments in seagrass beds of Bahia de la Ascension, Mexico examined the impact of different-sized artificial shelters upon survival of three juvenile size-classes of the Caribbean spiny lobster, Panulirus argus. The artificial shelters were concrete structures (casitas) that simulate lobster dens. In the tethering experiments, spiny lobster survival was generally higher in smaller than larger casitas, though the effect depended upon the relationship between lobster and shelter size. Thus, spiny lobster survival depends not only upon the availability of shelter, but also on the scaling between shelter size and lobster size. These results suggest that placement of appropriately-scaled …
The Least Tern In Virginia: Breeding Biology And Population Distribution, John William Akers
The Least Tern In Virginia: Breeding Biology And Population Distribution, John William Akers
Dissertations, Theses, and Masters Projects
No abstract provided.
A Numerical And Spatial Study Of The Meadow Vole, Microtus Pennsylvanicus, Margaret Whitney Higgins Bowker
A Numerical And Spatial Study Of The Meadow Vole, Microtus Pennsylvanicus, Margaret Whitney Higgins Bowker
Dissertations, Theses, and Masters Projects
No abstract provided.