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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Broad Spatial Trends in Osprey Provisioning, Reproductive Success, and Population Growth Within Lower Chesapeake Bay

Glass, Kenneth andrew 01 January 2008 (has links)
No description available.
2

Availability of Lead, Zinc, Copper, and Cadmium to the Peregrine Falcon (Falco peregrinus) from Waterfowl of the Craney Island Disposal Area

Davis, Douglas Stephen 01 January 1988 (has links)
No description available.
3

The peregrine falcon in Virginia: Survey of historic eyries and reintroduction effort

Gabler, Johannes Kurt 01 January 1983 (has links)
No description available.
4

Effects of Sub lethal Methylmercury Exposure on Pigment Coloration in a Model Songbird

Spickler, Jessica Lynn 01 January 2014 (has links)
No description available.
5

Golden-winged warbler (<em>Vermivora chrysoptera</em>) demographics and habitat use and the potential effects of land use change on golden-winged and cerulean warblers (<em>Dendroica cerulea</em>) in the Cumberland Mountains of Tennessee

Bulluck, Lesley Penfield 01 May 2007 (has links)
The golden-winged warbler (Vermivora chrysoptera) is an early successional Nearctic-Neotropical migrant songbird undergoing population declines range-wide. The Cumberland Mountains contain one of the southernmost populations where goldenwingeds occur in relatively high densities on old reclaimed surface mines. The three objectives of this research were to (1) describe the basic demography and habitat use of this population, (2) compare the demography of the Cumberland population to a population in Ontario, and (3) to model alternative land use scenarios and the impacts on both the golden-winged warbler and the cerulean warbler (Dendroica cerulean), another declining Nearctic-Neotropical migrant that occupies mature forests. Specifically, I modeled daily nest survival rate as a function of biologically meaningful covariates (Part 2) and the relative effects of habitat and demographic factors on territory size variation (Part 3) for the Tennessee population. There was some evidence of annual variation in nest survival rates and a decline throughout the nesting season, but I found little evidence that local habitat characteristics measurably affected nest survival. Territory size varied with the percent cover of vines and the number of snags. The single demographic factor related to territory size was nest success; birds with larger territories had a greater rate of nest success. I compared annual adult survival, fecundity, rate of population growth (λ), and mean time to extinction for Tennessee and Ontario populations (Part 4). Adult survival and fecundity were similar for the two populations such that predictions based on the theory of life history variation with latitude were not supported. Lambda estimates suggested that both populations were declining and I projected extirpation within 20-30 years without immigration. To further explore avian populations in the Cumberlands, I modeled coal mining, reclamation, and timber harvesting under a base-case scenario (as described by landowners and industries) as well as for alternatives that limited the amount of disturbance (Part 5). None of the scenarios were sustainable alternatives for cerulean and golden-winged warbler populations. My results suggest that future disturbances should be significantly limited to meet cerulean population goals and existing early successional habitat should be maintained and enhanced to sustain goldenwinged warbler populations.
6

Underwater observation and habitat utilization of three rare darters (Etheostoma cinereum, Percina burtoni, and Percina williamsi) in the Little River, Blount County, Tennessee

Jett, Robert Trenton 01 May 2010 (has links)
The Little River in Blount County is home to one of the richest darter faunas in East Tennessee. Increases in agriculture and development on several tributaries and the main stem of the Little River are suspected as causes for reduced abundance in fish populations. Earlier research on the Little River identified three species, Etheostoma cinereum (ashy darter), Percina burtoni (blotchside logperch), and P. williamsi (sickle darter), as having low densities. From May – October 2009, snorkel observations were made at 16 predetermined sites along the mainstem of the river to determine abundance and habitat association of these target species, as well as abundance of P. aurantiaca (tangerine darter) for comparison with historic surveys. All fish observed while snorkeling were identified and microhabitat measurements were taken at the location of all target species. Observations included 39 fish species, including 273 P. aurantiaca, 58 P. burtoni, and 7 P. williamsi. Etheostoma cinereum were not encountered during this study. Our observations documented that darter populations during 2009 were significantly different than historic populations, indicating that local populations of the target species have been negatively impacted since the historic survey. E. cinereum has been consistently difficult to collect on the Little River, and previous sampling efforts have observed this species with less frequency in the last 30 years. The absence of this species in this study may be an artifact of habitat degradation due to development and agriculture, two consecutive years of drought in 2007-2008, or potential sampling bias due to high flows in 2009. Habitat measurements documented that P. burtoni were frequently associated with gravel and cobble substrates. This habitat association is indicative of the feeding habits of P. burtoni who use their padded snout to flip small stones and feed on the aquatic insects found underneath. Turbidity was closely associated with river mile, with a consistent increase in turbidity at downstream sites in the watershed.
7

Underwater observation and habitat utilization of three rare darters (Etheostoma cinereum, Percina burtoni, and Percina williamsi) in the Little River, Blount County, Tennessee

Jett, Robert Trenton 01 May 2010 (has links)
The Little River in Blount County is home to one of the richest darter faunas in East Tennessee. Increases in agriculture and development on several tributaries and the main stem of the Little River are suspected as causes for reduced abundance in fish populations. Earlier research on the Little River identified three species, Etheostoma cinereum (ashy darter), Percina burtoni (blotchside logperch), and P. williamsi (sickle darter), as having low densities. From May – October 2009, snorkel observations were made at 16 predetermined sites along the mainstem of the river to determine abundance and habitat association of these target species, as well as abundance of P. aurantiaca (tangerine darter) for comparison with historic surveys. All fish observed while snorkeling were identified and microhabitat measurements were taken at the location of all target species. Observations included 39 fish species, including 273 P. aurantiaca, 58 P. burtoni, and 7 P. williamsi. Etheostoma cinereum were not encountered during this study. Our observations documented that darter populations during 2009 were significantly different than historic populations, indicating that local populations of the target species have been negatively impacted since the historic survey. E. cinereum has been consistently difficult to collect on the Little River, and previous sampling efforts have observed this species with less frequency in the last 30 years. The absence of this species in this study may be an artifact of habitat degradation due to development and agriculture, two consecutive years of drought in 2007-2008, or potential sampling bias due to high flows in 2009. Habitat measurements documented that P. burtoni were frequently associated with gravel and cobble substrates. This habitat association is indicative of the feeding habits of P. burtoni who use their padded snout to flip small stones and feed on the aquatic insects found underneath. Turbidity was closely associated with river mile, with a consistent increase in turbidity at downstream sites in the watershed.
8

Assessing Environmental Stress on the Loggerhead Sea Turtle (Caretta caretta) in Virginia Waters

Bellmund, Sarah A. 01 January 1988 (has links)
No description available.
9

Refining the Use of Stable Isotope Analysis in Detecting Wildlife Laundering

Guilfoyle, Kevin 01 January 2023 (has links) (PDF)
The international wildlife trade has caused significant declines in wild populations. Captive breeding can reduce the pressure on wild populations caused by overcollection, but if not properly monitored, wildlife laundering can lead to further population declines. Improving the forensic ability to detect wildlife laundering will assist in monitoring the wildlife trade and enforcing regulations, thereby aiding recovery of wild populations. Stable isotope analysis has grown in importance as a forensic tool, but improvements are needed. Here, stable isotope analysis (δ13C) on eggshells of captive bred and wild sourced island apple snails (Pomacea maculata) distinguished between the two; eggshells of captive bred snails were depleted in 13C relative to eggshells sourced from two wild populations. Thus, routine isotope sampling of eggshell material from purported captive breeding facilities can be used to identify discrepancies that would warrant further scrutiny. To address limitations of single-tissue stable isotope analysis as a forensic tool, I investigated between-tissue comparisons to differentiate between captive bred and wild sourced animals. The δ13C values of snail shell and foot muscle were significantly correlated in captive bred snails but not in wild caught snails. Between-tissue relationships therefore can detect wildlife laundering when animals are sampled in bulk. I also tested whether the use of hydroponically grown plants to reduce isotope variability in animal diets - and thereby in the tissues of the captive animals fed them - can increase the sensitivity of stable isotope analysis as a forensic tool. Kale grown hydroponically was significantly less variable in δ13C values than kale grown traditionally in soil. As predicted, P. maculata fed hydroponically grown kale had significantly less variable shell and foot δ13C values, and less variable δ15N foot values than snails fed traditionally grown kale. Combined, these experiments strengthen the viability of stable isotope analysis as a forensic tool capable of detecting signs of wildlife laundering.
10

Bird Conservation Value of Golf Courses

LeClerc, Joshua Elliott 01 January 2004 (has links)
No description available.

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