Thesis (Ph.D.) in Wildlife Ecology--University of Maine, 2007. / Includes vita. Includes bibliographical references (leaves 100-117).

<p>There have been many cases reported of amphibian populations declining. These are often due to anthropogenic factors such as habitat destruction and pollution. However, some eclines have not had an obvious cause and many of these have been investigated and found to be due to pathogenic disease. Batrachochytrium dendrobatidis is a recently described pathogen of frogs. The population declines that have been associated with chytridiomycosis have occurred in relatively undisturbed areas such as national parks. The declines tend to occur at higher altitudes or in colder climates. This is thought to be because of the frog immune system being slower at lower temperatures. This project gives an overview of chytrid infection in the Western Cape and at a small number of sites in the Northern Cape and Eastern Cape.</p>

Size fluctuations in amphibian populations at single breeding sites are related to variations in recruitment from the larval stage. However, overall patterns of abundance should be related to the pattern of recruitment success at the many sites where breeding occurs over a landscape. Recruitment patterns for six amphibian species, Ambystoma laterale, A. maculatum, Bufo americanus, Hyla versicolor, Pseudacris crucifer and Rana sylvatica, were investigated at multiple sites within the 10 km 2 Mont St. Hilaire nature reserve during 2001 and 2002. Amphibians bred at eighteen sites but recruitment occurred at only 8 and 11 sites in each year, respectively. Hydroperiod and predation were the most important determinants of recruitment. Four species suffered multiple recruitment failures both years. However, when sites were considered collectively, recruitment was successful for all species because of asynchronous recruitment patterns across heterogeneous sites. Amphibian population dynamics may be stochastic at any single site but recruitment success at multiple sites is a plausible predictor of abundance and trends in regional population persistence.

<p>There have been many cases reported of amphibian populations declining. These are often due to anthropogenic factors such as habitat destruction and pollution. However, some eclines have not had an obvious cause and many of these have been investigated and found to be due to pathogenic disease. Batrachochytrium dendrobatidis is a recently described pathogen of frogs. The population declines that have been associated with chytridiomycosis have occurred in relatively undisturbed areas such as national parks. The declines tend to occur at higher altitudes or in colder climates. This is thought to be because of the frog immune system being slower at lower temperatures. This project gives an overview of chytrid infection in the Western Cape and at a small number of sites in the Northern Cape and Eastern Cape.</p>

Thesis (M.S.)--Marshall University, 2008. / Title from document title page. Includes abstract. Document formatted into pages: contains 64 p. : ill. Includes bibliographical references (p. 60-64).

Magister Scientiae - MSc / There have been many cases reported of amphibian populations declining. These are often due to anthropogenic factors such as habitat destruction and pollution. However, some eclines have not had an obvious cause and many of these have been investigated and found to be due to pathogenic disease. Batrachochytrium dendrobatidis is a recently described pathogen of frogs. The population declines that have been associated with chytridiomycosis have occurred in relatively undisturbed areas such as national parks. The declines tend to occur at higher altitudes or in colder climates. This is thought to be because of the frog immune system being slower at lower temperatures. This project gives an overview of chytrid infection in the Western Cape and at a small number of sites in the Northern Cape and Eastern Cape. / South Africa

No description available.

We compared techniques for assessing nutritional condition in 3 groups of terrestrial salamanders. We measured variability in species richness and relative abundance before harvest at 5 sites in the Jefferson National Forest of southwest Virginia and compared the effects of 7 silvicultural treatments on terrestrial salamander richness and relative abundance at 1 site. / Master of Science

No description available.

No description available.