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Full-Text Articles in Life 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 …


Determination Of Dispersal Patterns Of The Small-Mouthed Salamander (Ambystoma Texanum) In Eagle Creek Park (Indianapolis, In), Stacey Diane Summitt May 2009

Determination Of Dispersal Patterns Of The Small-Mouthed Salamander (Ambystoma Texanum) In Eagle Creek Park (Indianapolis, In), Stacey Diane Summitt

Undergraduate Honors Thesis Collection

Urbanization and the increasing threat of habitat fragmentation are contributing to the significant declines in amphibian populations world-wide. Ambystomatid species are particularly susceptible to habitat fragmentation because they migrate yearly across upland forests to their breeding sites. Habitat changes could be altering the genetic structure in these species; however few studies have focused on this topic and more generally, examined the dispersal patterns of Ambystomatids. In 2003, Clark, Cripe, and Stachniw conducted a study on “Metapopulation Structure of Ambystoma texanum in Eagle Creek Park (Indianapolis, IN) and the Potential for Gene Flow.” They hypothesized that distance limits the dispersal of …


Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann Apr 2009

Differential Response Of Amp Activated Protein Kinase (Ampk) And Hsp70 To Temperature Stress In The Gastropod, Nucella Lapillus, Emily Zimmermann

All Theses And Dissertations

Populations of the gastropod Nucella lapillus are polymorphic for shell color, with light-colored shells predominating on warmer, wave-protected shores and dark-colored shells limited primarily to cooler, wave-exposed shores. During thermal stress, darker shells attain higher body temperatures than lighter shells. These results suggest that heat stress may determine field distribution patterns. However, there is currently little evidence of physiological consequences of thermal stress in these organisms. Following the guiding hypothesis that heat stress leads to cellular energy depletion, we explored whether the central energy regulator AMP-activated Protein Kinase (AMPK) is activated by heat stress. We compared this response in both …


Granite Rock Outcrops: An Extreme Environment For Soil Nematodes?, Erin Austin, Katharine Semmens, Charles Parsons, Amy M. Treonis Mar 2009

Granite Rock Outcrops: An Extreme Environment For Soil Nematodes?, Erin Austin, Katharine Semmens, Charles Parsons, Amy M. Treonis

Biology Faculty Publications

We studied soil nematode communities from the surface of granite flatrock outcrops in the eastern Piedmont region of the United States. The thin soils that develop here experience high light intensity and extreme fluctuations in temperature and moisture and host unique plant communities. We collected soils from outcrop microsites in Virginia (VA) and North Carolina (NC) in various stages of succession (Primitive, Minimal, and Mature) and compared soil properties and nematode communities to those of adjacent forest soils. Nematodes were present in most outcrop soils, with densities comparable to forest soils (P > 0.05). Nematode communities in Mature and Minimal soils …


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 …


A Sustainable Future, David A. Bainbridge Jan 2009

A Sustainable Future, David A. Bainbridge

David A Bainbridge

A key step toward a more sustainable future is beginning the discussion of what this would entail. What are the defining characteristics of sustainability? How could we get there? What benefits and costs might this involve?