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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

Terrestrial habitat use by pool-breeding amphibians in a suburban landscape /

Regosin, Jonathan V. January 2003 (has links)
Thesis (Ph.D.)--Tufts University, 2003. / Adviser: J. Michael Reed. Submitted to the Dept. of Biology. Includes bibliographical references (leaves 124-134). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
2

Efficacy of DNA sampling to monitor population abundance of black bears in the southern Appalachians

Settlage, Katie E. January 2005 (has links) (PDF)
Thesis (M.S.) -- University of Tennessee, Knoxville, 2005. / Title from title page screen (viewed on September 2, 2005). Thesis advisor: Frank T. van Manen. Document formatted into pages (xiii, 91 p. : ill., col. maps). Vita. Includes bibliographical references (p. 80-87).
3

A system model for white-tailed deer population management in northeastern Washington

Kato, Aki, January 2007 (has links) (PDF)
Thesis (M.S.)--Washington State University, August 2007. / Includes bibliographical references (p. 31-33).
4

Rapid endangered species assessment : a novel approach to improve extinction risk assessments in poorly known species /

Bianchi, Carlos A. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2010. / Printout. Includes bibliographical references (leaves 155-180). Also available on the World Wide Web.
5

Estimating the distribution of demand for Antarctic krill (Euphausia superba) from land-based predators at South Georgia /

Swarbrick, Matthew L. January 2007 (has links)
Thesis (Ph.D.) - University of St Andrews, May 2007.
6

Incorporating model selection and decision analysis into population dynamics modeling /

Ward, Eric John, January 2006 (has links)
Thesis (Ph. D.)--University of Washington, 2006. / Vita. Includes bibliographical references (leaves 127-139).
7

Social organisation and population demographics of lions (Panthera leo) in the Okavango Delta

Kotze, Christen Robynne January 2016 (has links)
thesis submitted to the School of Animal, Plant and Environmental Sciences, Faculty of Science, University of the Witwatersrand, Johannesburg in fulfillment of the requirements for the degree of Masters in Science. Johannesburg 2016. / The Okavango Delta in northern Botswana contains the largest, unfenced lion population in southern Africa, and is one of the most important population strongholds for the species on the continent. Despite its conservation importance, however, little information has been published on the drivers of lion ecology in this unique wetland ecosystem. In the Okavango Delta, the annual flood pulse causes dramatic seasonal contractions of available dry land, and consequently variable distribution and abundance of prey. Lions must therefore adapt to a dynamic environment not only on an annual basis, but also on a longer time-scale as inundation patterns cycle from periods of low to high floods. The main aim of the study was to determine which social and ecological factors were most important in determining lion population demographics and social organisation in the unique wetland environment of the Okavango Delta. Data were intensively collected on demographic rates and social organisation of five resident lion prides in the south-western Okavango Delta from 1997 to 2004, during which inundation patterns shifted from low to high floods. We investigated the effects of two ecological factors, namely prey availability and flood extent, and one social factor, namely intra-specific competition, on lion social organisation and population demographics. Lions occurred at high densities, and the population was regulated socially and not by resource limitation. Our results indicated that competition with neighbours exerted the most extensive influence on the lion population and significantly affected the survival of young cubs and reproductive rates. Competition reduced pride size, but contrary to our expectations, also negatively influenced sub-group size, indicating that territorial disputes do not drive sub-group patterns in the Okavango Delta. Prey availability did not appear to be an important limiting factor for the population, and group sizes were inversely related to prey availability, most likely due to habitat saturation resulting in higher levels of recruitment. Prey availability only influenced survival of young cubs, which are most vulnerable to nutritional stress. Higher levels of flooding led to smaller pride and sub-group sizes, indicating that higher flood levels for extended periods may lead to a decline in lion densities due to increased competition for available dry land. While flooding exerted no direct effect on demographic rates, we posit that habitat conversion during high flood cycles causes a decline in prey, resulting in a time-lagged effect on the lion population. Our results show that during low flood cycles when herbivore abundance is high, lions occur at high densities and are largely self-regulated. However, as flood levels increase, prey availability declines and lions are placed under increasing pressure for space and resources, which could ultimately lead to population decline. From a conservation perspective, the south-western Okavango Delta population is thus most vulnerable during periods of high floods, when lion densities naturally decline, and lions may be pushed towards the veterinary fence where human-lion conflict is high. Future studies should focus on how anthropogenic threats around the Okavango Delta threaten the viability of the lion population in this conservation area, and seek to secure important corridors to neighbouring populations. Keywords: lion, Panthera leo, social organisation, pride size, population demographics, survival reproduction, Okavango Delta, flooding, competition, prey abundance / LG2017
8

Optimising camera trap density and position to determine medium and large mammal species richness and occupancy on the Cape Peninsula, South Africa

Colyn, Robin January 2016 (has links)
Thesis (MTech (Nature Conservation))--Cape Peninsula University of Technology, 2016. / Largely due to anthropogenic causes, biodiversity and particularly species diversity is changing at an extraordinary rate, with declines in species abundance, community composition and extinction risk being of crucial concern. Monitoring of state variables of biodiversity such as species richness and occupancy are of significant importance in determining the severity of threats placed on species, populations and communities. As a non-invasive monitoring method camera traps are noted as being an effective, accurate and rapid means of compiling species richness estimates of medium to large terrestrial mammals. However, crucial elements of camera trap survey design are rarely empirically addressed, which has questioned the need for a standardised camera trapping protocol. Table Mountain National Park (TMNP) is a protected area that is under serious anthropogenic pressure through urban and peri-urban development. Although it is the last refuge for a number of large mammal species on the Cape Peninsula, current mammalian species richness knowledge within the TMNP are limited. Accurate and current species richness estimates are therefore needed within TMNP and more specifically the Cape of Good Hope (CoGH), which exclusively hosts a number of medium and large mammal species. The aims of this study were to optimise a camera survey protocol for the Peninsula region, with a focus on camera density, placement and survey duration that will enable accurate estimations of medium to large mammal species richness and occupancy.
9

Factors leading to cannibalism in Lytechinus variegatus (Echinodermata: Echinoidia) in the laboratory

Richardson, Cristina M. January 2010 (has links) (PDF)
Thesis (M.S.)--University of Alabama at Birmingham, 2010. / Title from PDF t.p. (viewed July 20, 2010). Additional advisors: Robert U. Fischer, John M. Lawrence, Ken B. Marion. Includes bibliographical references (p. 55-59).
10

Assessing estimators of feral goat (Capra hircus) abundance

Tracey, John Paul. January 2004 (has links)
Thesis (M. Appl. Sci.)--University of Canberra, 2004. / Title from PDF title page (viewed on July 20, 2005). Includes bibliographical references (p. 129-146).

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