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Full-Text Articles in Animal Sciences

Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora Dec 2009

Population Ecology And Reproductive Biology Of The Diamondback Watersnake, Nerodia Rhombifer (Serpentes: Colubridae), In Southernmost Texas, Ruben D. Zamora

Theses and Dissertations - UTB/UTPA

Nerodia rhombifer is a polytypic, semi-aquatic snake with a broad geographical distribution ranging from the American Midwest southward to Chiapas, Mexico. Although relatively abundant throughout much of its range, few ecological studies of the species have been conducted. This study provides basic population ecology information in a subtropical habitat. Population data were obtained in a mark-recapture study at Santa Ana National Wildlife Refuge, Hidalgo County, Texas, from August 1995 to December 1998. Specimens taken elsewhere in Hidalgo County provided information on the reproductive biology. This study provides the first absolute density estimates from anywhere within the species’ range. Quantitative information …


Population Assessment Of Eastern Oysters (Crassostrea Virginica) In The Seaside Coastal Bays, Paige G. Ross, Mark Luckenbach Feb 2009

Population Assessment Of Eastern Oysters (Crassostrea Virginica) In The Seaside Coastal Bays, Paige G. Ross, Mark Luckenbach

Reports

Declines of oyster populations and commercial harvest from the Virginia seaside coastal bays have followed similar patterns, though not as severe, as those in Chesapeake Bay. High prevalence of Dermo disease (Perkinsus marinus) and MSX disease (Haplosporidium nelsoni) coupled with over harvest and habitat destruction have dramatically reduced populations. Nevertheless, there are several promising signs that significant enhancement of the population could be achieved with well conceived restoration efforts. Oyster habitat and population distribution were examined in the coastal bay system on the seaside of the Eastern Shore of Virginia. This system is composed of barrier islands, salt marshes, broad …


Evaluation Of Pre-Spawning Movements Of Anadromous Alewives In The Ipswich River Using Radiotelemetry, Holly J. Frank Jan 2009

Evaluation Of Pre-Spawning Movements Of Anadromous Alewives In The Ipswich River Using Radiotelemetry, Holly J. Frank

Masters Theses 1911 - February 2014

Conserving and restoring anadromous fish populations is an important research and management priority. For conservation to be effective, researchers must understand the behavior of the fish they seek to restore. Telemetry has allowed researchers to understand the upstream migrations of these fish in freshwater, how migration patterns vary, and if there is a relationship between behavior and environmental variables. In the northeastern United States, alewife (Alosa pseudoharengus), one of two species collectively referred to as river herring, has historically been an important component of coastal rivers. However, populations of these fish have experienced recent declines, and a commonly used method …


Conservation Implications Of A Marbled Salamander, Ambystoma Opacum, Metapopulation Model, Ethan B. Plunkett Jan 2009

Conservation Implications Of A Marbled Salamander, Ambystoma Opacum, Metapopulation Model, Ethan B. Plunkett

Masters Theses 1911 - February 2014

Amphibians are in decline globally and a significantly greater percentage of ambystomatid salamander species are in decline relative to other species; habitat loss contributes significantly to this decline. The goals of this thesis is to better understand extinction risk in a marbled salamander (ambystoma opacum) population and how forestry effects extinction risk. To achieve this goal we first estimated an important life history parameter (Chapter 1) then used a metapopulation model to estimate population viability and determine what aspects of their life history put them most at risk (Chapter 2) and finally predicted extinction risk in response to hypothetical forestry …


Variation In Winter Estuarine Habitat Use By Bluefish In Northeastern Florida With Implications For Growth And Condition, John S. Murt Jan 2009

Variation In Winter Estuarine Habitat Use By Bluefish In Northeastern Florida With Implications For Growth And Condition, John S. Murt

Masters Theses 1911 - February 2014

Age and growth were determined from otoliths for 181 juvenile bluefish, Pomatomus saltatrix, collected using a variety of gear in northeast Florida during 2003 and 2005. Three distinct cohorts were identified recruiting to the near shore waters during spring, summer and fall. Growth rates were high regardless of cohort or season. To compare pre- and post-recruitment growth rates, models were fit to individual growth trajectories using change point analysis. Post-estuarine growth rates were generally higher. Growth rates and hatching times were within the range of those obtained in other bluefish studies conducted at higher latitudes. As this is the only …


Records Of Aquatic Beetles (Helophoridae, Hydrophilidae, Hydrochidae, Dytiscidae) And Physico-Chemical Parameters In A Natural Lake (Artvin, Turkey), Ümi̇t İncekara Jan 2009

Records Of Aquatic Beetles (Helophoridae, Hydrophilidae, Hydrochidae, Dytiscidae) And Physico-Chemical Parameters In A Natural Lake (Artvin, Turkey), Ümi̇t İncekara

Turkish Journal of Zoology

Some ecological requirements of aquatic Coleoptera species were studied in a natural lake. Water beetle samples, collected in 2007 from the National Park Sahara-Karagöl belonging to the families Helophoridae, Hydrophilidae, Hydrochidae, and Dytiscidae were identified and listed. Both physical (conductivity and temperature) and chemical (pH, dissolved oxygen, total dissolved solids, hardness, organic matter, chloride, phosphate, and some metal ions) parameters of the inhabited water were measured.


Ecological Succession Of Freshwater Ostracoda (Crustacea) In A Newly Developed Rheocrene Spring (Bolu, Turkey), Okan Külköylüoğlu Jan 2009

Ecological Succession Of Freshwater Ostracoda (Crustacea) In A Newly Developed Rheocrene Spring (Bolu, Turkey), Okan Külköylüoğlu

Turkish Journal of Zoology

Six species of ostracod (Candona neglecta, Heterocypris incongruens, Ilyocypris bradyi, Darwinula stevensoni, Pseudocandona compressa, and Psychrodromus olivaceus) were collected from a newly developed spring between October 2001 and October 2004. The first 5 species have cosmopolitan distribution in the Holarctic region. The ratio of non-cosmopolitan to cosmopolitan species (called 'pseudorichness') was 0.2, suggesting dominance of cosmopolitan species. Among the species, C. neglecta displayed the highest tolerance to 6 different environmental variables, although its estimated optimum values varied. Except foor redox potential and salinity, optimum values for H. incongruens were the highest. High tolerance and optimum values seemed to provide more …