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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.
41

Habitat selection by American martens (Martes americana) in coastal northwestern California /

Slauson, Keith M. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2004. / Typescript (photocopy). Includes bibliographical references (leaves 77-86). Also available on the World Wide Web.
42

Habitat associations of the long-nosed potoroo (potoroos tridactylus) at multiple spatial scales

Norton, Melinda A. January 2009 (has links)
Thesis (M.Sc. (Res.))--University of Wollongong, 2009. / Typescript. Includes bibliographical references: leaf 147-159.
43

Endangered species conservation in the Upper Midwest an economic perspective /

Langner, Linda L. January 1984 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1984. / Typescript. Vita. Includes bibliographical references (leaves 222-225).
44

The convention on international trade in endangered species of wild fauna and flora political or conservation success? /

Trexler, Mark Charles. January 1990 (has links)
Thesis (Ph. D.)--University of California, Berkeley, 1990. / Includes bibliographical references (leaves 156-169).
45

Health and disease status of Australia's most critically endangered mammal the Gilbert's potoroo (Potorous gilbertii) /

Vaughan, Rebecca. January 2008 (has links)
Thesis (Ph.D.)--Murdoch University, 2008. / Thesis submitted to the Faculty of Health Sciences. Includes two articles published in the Journal of Zoo and Wildlife Medicine, 2007 v. 34 (4) p. 567-573 and March 17, 2008. Includes bibliographical references (leaves 273-312)
46

Herpetofaunal communities in agroecosystems : the effect of farm management style /

Herman, John. January 2005 (has links)
Thesis (M.S.)--University of Toledo, 2005. / Typescript. "A thesis [submitted] as partial fulfillment of the requirements of the Master of Science degree in Biology." Bibliography: leaves 45-50.
47

Population demography, resource use, and movement in cooperatively breeding Micronesian Kingfishers /

Kesler, Dylan C. January 1900 (has links)
Thesis (Ph. D.)--Oregon State University, 2006. / Printout. Includes bibliographical references (leaves 173-195). Also available on the World Wide Web.
48

Persistence and abundance of the Western Grebe (Aechmophorus occidentalis) in Alberta

Erickson, Mara Elaine. January 2010 (has links)
Thesis (M. Sc.)--University of Alberta, 2010. / Title from pdf file main screen (viewed on July 8, 2010). A thesis submitted to the Faculty of Graduate Studies and Research in partial fulfillment of the requirements for the degree of Master of Science in Ecology, Department of Biological Sciences, University of Alberta. Includes bibliographical references.
49

Gut throughput rate and satiation of the invasive Lionfish (Pterois volitans) and its potential impact on an endemic, endangered Labrid fish Halichoeres socialis

Garner, James Graham 31 July 2017 (has links)
The invasive Indo-Pacific Lionfish Pterois volitans has been recognized as a severe threat to indigenous fish species on Caribbean reefs. Previous studies have identified an extensive variety of Caribbean fishes in the stomachs of lionfish, but few have tried to quantify the impact these invaders could have on endemic or threatened species. The threatened Labrid fish Halichoeres socialis has been identified as the primary component of lionfish diet in Belizean lagoonal reef systems. This study aims to answer two questions: what is the average maximum number of prey-fish a lionfish can consume in one sitting, and at what rate can these lionfish pass a meal of three prey fish completely? To test lionfish satiation, the subjects were fed as many Pseudohemiculter dispar (a commercially available surrogate) as they could eat within a fifteen-minute window. During the digestion rate experiment, lionfish were fed three similarly sized P. dispar and allowed to digest in 3, 6, 9, 12, 15, 19, and 24 hour blocks. From observing prey throughput under near optimal laboratory conditions, the maximum potential impact of lionfish on native populations of Caribbean reef dwelling fishes can be estimated. Given the volume and mass of prey items consumed in this study between 593 and 4658 individual H. socialis could be consumed by a single lionfish in one year. Coupled with further investigation into H. socialis stock numbers, lionfish (P. volitans) could be considered a potentially immanent threat to fishes that exhibit body morphometrics like those of H. socialis at any stage of their life-history.
50

Seasonal movement and activity patterns of the endangered geometric tortoise, psammobates geometricus

Van Bloemestein, Ulric Patrick January 2005 (has links)
Magister Scientiae (Biodiversity and Conservation Biology) / Due to the critical status of Psammobates geometricus and the vulnerability of their habitat, there is a need to allocate areas for their protection. The aim of this study was to provide information on the space requirements and activity level of geometric tortoises to facilitate future conservation efforts. The thread-and-spool method was used to compare short-term movements, habitat utilisation, and activity patterns of male and female tortoises over 15 and 20 days respectively, in autumn and spring. Through radiotelemetry, the long-term movements of 10 male and 11 female tortoises were evaluated from April 2002 to April 2003. Locality data for the short-term and long-term studies were used to calculate the size of activity areas and home ranges as minimum convex polygons and fixed kernel estimates. Male and female geometric tortoises were active throughout the year, and maintained a high level of activity in autumn and in spring. However, females were more active than males were in spring. Females may require more resources, particularly food, in spring when they produce eggs. Although males and females travelled similar distances in autumn and in spring, males displaced further than females displaced in both seasons. The movement path for males was often linear, perhaps because this path may enhance their opportunities to encounter females. Geometric tortoise males were substantially smaller than females, which may explain why the distances that males moved and displaced in spring were negatively correlated to environmental temperature. In autumn, when temperatures were lower than in spring, the distance travelled by males was not correlated to temperature. However, in autumn female displacement showed a positive correlation with environmental temperature. Geometric tortoises showed large inter-individual variation in home range size, which may contribute to the fact that home range size did not differ among the three different habitat types: mature renosterveld, burned renosterveld and the old agricultural fields. Average home range size was 11.5 ha for 95% fixed kernel estimates, and 7.0 ha for minimum convex polygon estimates. Body size influenced the home range size of female geometric tortoises, but had no effect on the home range size of male tortoises. Females had larger home ranges than male tortoises had, possibly because females were larger, but reproductive requirements of females may have played a role. During the dry season, home range size increased when compared to the wet season. The larger home range during the dry season, which is associated with high temperatures, may be related to a reduction in resource availability. The fewer resources available, the greater the distance the tortoises would need to travel in order to acquire the necessary resources. The small home range in the wet season may indicate an abundance of resources, but it may also be that large pools of standing water restrict the movements of tortoises. Understanding the spatial and habitat requirements of P. geometricus will help to assess the viability of populations in disturbed and highly fragmented areas, and contribute to the conservation efforts for this endangered species. / South Africa

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