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Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum May 2022

Detection, Occupancy, Abundance, And Mercury Accumulation Of The Alligator Snapping Turtle (Macrochelys Temminckii) In Texas, David Rosenbaum

Electronic Theses and Dissertations

Land use practices and physical alterations of ecosystems result in habitat loss and fragmentation, while chemical alterations, such as pollutant input, reduce habitat quality and health of exposed organisms. Here, I investigated the effects of watershed- and local-scale environmental variables on the occupancy, abundance, and mercury accumulation of a threatened aquatic species (Macrochelys temminckii, i.e., alligator snapping turtle) within the southwestern periphery of its distribution. Hierarchical modeling suggested the distribution of the species is more affected by watershed-scale land-cover than local habitat, and provided a baseline estimate of average species abundance across its range in eastern Texas. Abundance …


Land Use Influences Along Elevation Gradient On Macroinvertebrate Communities, Brittany Sprout Jan 2020

Land Use Influences Along Elevation Gradient On Macroinvertebrate Communities, Brittany Sprout

Electronic Theses and Dissertations

Land use activities have caused disturbances that affect the quality of freshwater ecosystems worldwide. How the influences of land use along an environmental gradient and the associated environmental variables that may influence stream diversity and function is unclear. We address these issues by studying biodiversity, abundance, and functional diversity of macroinvertebrates across different land types along a gradient in Colorado, USA. We also address how diversity may change along an elevation gradient by analyzing previously published macroinvertebrate research. We found evidence that land use and disturbance are stronger explanations of changes in macroinvertebrate communities, rather than elevation. Functional trait patterns …


The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley Aug 2018

The Population Ecology And Behavior Of The Cave Salamander, Eurycea Lucifuga (Rafinesque, 1822)., Joseph Gavin Bradley

Electronic Theses and Dissertations

The Cave Salamander, Eurycea lucifuga (Rafinesque, 1822), is a little-known species, yet a common inhabitant of caves in the eastern United States. Salamanders are often important components of ecological communities and ecosystems, influencing critical processes such as nutrient cycling and community composition through their predation on invertebrates. Cave-dwelling salamanders such as E. lucifuga may thus appreciably influence the relatively simple ecosystems and communities of caves. Any such influence may be particularly important because these habitats and the organisms that reside in them are often of conservation concern. I used non-invasive methods to study the demographics, movements, and habitat selection of …


An Examination Of Plant Community Composition In Six Carolina Bays On The Coastal Plain Of South Carolina, Katherine L. Altman-Goff Jan 2016

An Examination Of Plant Community Composition In Six Carolina Bays On The Coastal Plain Of South Carolina, Katherine L. Altman-Goff

Electronic Theses and Dissertations

Historically high rates of human impact and recent Supreme Court cases, which have affected the regulation of geographically isolated wetlands in the United States, suggest that Carolina bays may be at high risk of human impacts in the future. Conservation efforts should be established based on applied ecological data and, if regulations by state and federal agencies are unable to conserve Carolina bay wetlands, it may be important to prioritize individual bays for preservation on protected lands. I examined plant community composition, diversity, richness, and rarity and soil parameters in six Carolina bays across South Carolina, using a replicated ecological …


Spatial And Temporal Variability In The Carrion Insect Community: Using Blow Flies (Family: Calliphoridae) As A Model System To Study Coexistence Mechanisms At Multiple Scales, Jennifer Yvonne Rosati Jan 2014

Spatial And Temporal Variability In The Carrion Insect Community: Using Blow Flies (Family: Calliphoridae) As A Model System To Study Coexistence Mechanisms At Multiple Scales, Jennifer Yvonne Rosati

Electronic Theses and Dissertations

Resource partitioning can lead to species coexistence. In a field study, temporal and spatial partitioning were examined by testing the effects of season and habitat on the structure of the blow fly community on domestic pig carcasses, Sus scrofa domesticus in southwestern Ontario, Canada. Blow fly communities did not differ between field and forest habitats, however there were seasonal differences. Fall was characterized by having more species and higher levels of species evenness, diversity, and niche overlap than spring and summer. On a finer scale, effects of arrival order were examined in laboratory experiments with three blow fly species: Phormia …


Ecology Of Glacial Relict Fishes In South Dakota's Sandhills Region, Eli Felts Jan 2013

Ecology Of Glacial Relict Fishes In South Dakota's Sandhills Region, Eli Felts

Electronic Theses and Dissertations

Native stream fish zoogeography has changed substantially across North America during the last century as habitat degradation, stream fragmentation and introductions of nonnative species have led to numerous extinctions, extirpations and altered distributions. Insufficient information regarding imperiled species often results in reactive, rather than proactive, management, and knowledge of species status and ecology is critical in identifying conservation priorities. South Dakota populations of three dace species (northern redbelly dace Chrosomus eos, finescale dace Chrosomus neogaeus, and pearl dace Margariscus margarita) are relict of Pleistocene Glaciation and are isolated from the northern core of their distribution, but little information exists regarding …


Raptor Use Of The Idaho National Engineering Laboratory, Richard Wayne Hansen Jan 1994

Raptor Use Of The Idaho National Engineering Laboratory, Richard Wayne Hansen

Electronic Theses and Dissertations

Raptors are high trophic-level predators, and thus sensitive to environmental change. I conducted a basic ecological study of raptors using the Idaho National Environmental Laboratory (INEL), in southeastern Idaho, between 1991 and 1993 to assess effects of human activity on the site. Results were compared to previous raptor studies conducted on the INEL from 1974-1976 and in 1982, as well as with studies of rough-legged hawks, long-eared owls, and burrowing owls conducted during the late 1970’s and early 1980’s. Road-side raptor surveys were conducted from January through May in 1992 and 1993. Principle species recorded were rough-legged hawks, red-tailed hawks, …