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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

Fragmented landscape and fragmented law : threatened species management in South Australia /

Reeve, Martin. January 1998 (has links) (PDF)
Thesis (M. Env. Sc.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1999. / Includes bibliographical references (leaves 124-134).
2

Using insect responses to anthropogenic disturbance to improve land management and conservation planning decisions

Sanford, Monte Paul. January 2007 (has links)
Thesis (Ph. D.)--University of Nevada, Reno, 2007. / "December 2007." Includes bibliographical references. Online version available on the World Wide Web.
3

Lidské preference živočišných druhů a jejich vliv na druhovou ochranu / Human preference to animal species and its impact on species conservation

Marešová, Jana January 2012 (has links)
The dissertation thesis deals with human aesthetic preference to other species and its anthropological and conservation aspect. The aesthetic preference to animal species has rarely been systematically studied before and quantitative analyses, especially on a fine taxonomic scale did not exist. On the other hand, it was known that attractive species often receive more support for their conservation. From these simple facts rose the idea to test human aesthetic preference to snake species (and consequently to species across major vertebrate taxa) and use this quantified preference to explain the conservation effort devoted to captive breeding worldwide (measured as size of zoo populations). We confirmed that the perceived attractiveness (preference and/or species' body size) succesfully predicts the size of zoo populations across mammal, bird and reptile taxa. On contrary, we found no effect of the IUCN listing of the species. To find out whether we work with Czech students' preference only or we may generalize to other populations, we carried out the same experiment to determine human preference to boas and pythons in eight cultures of five continents. Despite profound differences of the studied ethnics, we revealed a considerable agreement. Moreover, we found an agreement between pre-school...
4

Quality assessment of cryopreserved spermatozoa of the blesbok (Damaliscus pygargus phillipsi), blue wildebeest (Connochaetes taurinus) and African buffalo (Syncerus caffer)

Mynhardt, Neil Philip 22 August 2012 (has links)
M.Sc. / Climate change, loss of habitat and over-exploitation of natural resources as well as the introduction of invasive alien species through human activities are resulting in an ever increasing risk of extinction of many plant and animal species. There are two major approaches to conserving threatened and endangered species. Firstly the large scale preservation of natural habitat and ecological processes, thereby protecting the species inhabiting the habitat. The second approach involves the ex-situ breeding of rare and endangered species. It is estimated that in the next 200 years approximately 800 mammalian species will require the assistance of breeding programs to ensure long term genetic viability. Biological Resource Banks (BRB) can potentially contribute to this challenge by providing a source of genes that can be used to counter the effects of external selection pressures, genetic drift and inbreeding depression in small or fragmented populations. These banks commonly contain biological materials such as cryopreserved sperm, embryos and cell cultures mainly as genetic and research resources. . Biological resource banks can potentially use these cryopreserved gametes together with assisted reproductive technologies (ART), such as artificial insemination (AI), in vitro fertilisation (IVF), embryo transfer (ET), intracytoplasmic sperm injection (ICSI) and nuclear transfer (NT) to maintain genetic heterogeneity in ex-situ and wild populations. Ascertaining the appropriate protocols for developing the ARTs necessary for non-domestic species is one of the major challenges faced by reproductive physiologists. Typically, there is very little available information about the processing of semen, the effects of diluents, concentration and type of cryoprotectants and freeze-thaw methods for sperm samples of non-domestic species. Procedures proven to be highly effective in humans and laboratory or domestic species, are frequently adopted and modified for use in related wildlife species. It is thus necessary to gain knowledge of the reproductive physiology of wildlife species in order to define effective protocols for the cryopreservation of biomaterials which assists in the conservation of South Africa‘s diverse wildlife species. Sperm quality assessment is a useful tool for assessing the reproductive health of free-ranging populations as well as for selecting individuals for future assisted reproduction programs.

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