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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

Reintroduction ecology of mala (Lagorchestes hirsutus) and merrnine (Lagostrophus fasciatus) at Shark Bay, Western Australia

Hardman, Blair, January 2006 (has links)
Thesis (M. Env. Mgt.)--Edith Cowan University, 2006. / Title from PDF title page (viewed on Apr. 16, 2007). Includes bibliographical references (p. 88-97).
2

The ecology and conservation biology of the yellow-footed rock-wallaby /

Sharp, Andy. January 2002 (has links) (PDF)
Thesis (Ph. D.)--University of Queensland, 2002. / Includes bibliographical references.
3

Cellular immune responses of marsupials : family Macropodidae

Young, Lauren Jill, University of Western Sydney, College of Science, Technology and Environment, School of Science, Food and Horticulture January 2002 (has links)
This thesis describes a comprehensive study of the cellular responses of a number of endangered marsupial species with a principal focus on the tammar wallaby (Macropus eugenii) as a model macropod species. The development of in vitro experimental assays for the assessment of immune responses in this model species are described, which provided a set of benchmarks for comparisons with other members of the Macropodidae and with eutherian mammals. Once this data was collected and protocols were established, the study was extended to include investigations of the immune responses in opportunistic samples obtained from the Rufous Hare-wallaby (Lagorchestes hirsutus), the Long-footed potoroo ( Potorous longipes) and the more common, but nonetheless still vulnerable, Long-nosed potoroo (Potorous tridactylus) with a view to investigating their apparent susceptibility to infection with intracellular pathogens, particularly mycobacterial species. The findings from the application of these assays suggest that the cellular immune responses of these species are relatively complex and involve a level of sophistication that rivals their eutherian counterparts. Specifically peripheral blood and tissue leukocytes were morphologically similar to those of other mammals, with the exception of tammar wallaby monocytes that appeared to contain few lysosomal granules, and the basophils of the Rufous Hare-wallaby that contained very large atypical granules. The overall findings of this study suggest that the immune systems of macropod species possess most of the sophistication associated with that of eutherian mammals. Whilst some differences were apparent in cells and their products in the test species, no single factor common to all macropods was identified as a cause for immune dysfunction. It appears likely that as yet undefined factors related to their confinement rather than an inherent defect in their immunocapacity is responsible for the apparent disease susceptibility of these animals. / Doctor of Philosophy (PhD)
4

Reintroduction biology of yellow-footed rock-wallabies (Petrogale xanthopus celeris and P. x. xanthopus)

Lapidge, Steven James. January 2001 (has links)
Thesis (Ph. D.)--University of Sydney, 2002. / Title from title screen (viewed Apr. 24, 2008). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Biological Sciences, Faculty of Science. Degree awarded 2002; thesis submitted 2001. Includes bibliography. Also available in print form.
5

Reintroduction biology of yellow-footed rock-wallabies (Petrogale xanthopus celeris and P. x. xanthopus)

Lapidge, Steven James. January 2001 (has links)
Thesis (Ph. D.)--University of Sydney, 2001. / Title from PDF title page (viewed on Aug. 10, 2005). Appendix 2 lacking in electronic version. Includes bibliographical references.
6

T-cell development in the Tammar wallaby (Macropus eugenii)

Zuccolotto, Peter, University of Western Sydney, Nepean, School of Science January 2000 (has links)
Marsupials and eutherians are the two principal groups of modern mammals. Mammalian immunological studies, to date, have focused on eutherian systems with little or no comprehensive work having been carried out on marsupials. This project investigates the functional and developmental aspects of T-cell responses in the marsupial, Macropus eugenii (Tammar wallaby) in both adults and pouch young at various stages of development. Determination of the age at which the Tammar wallaby immune system becomes competent has been examined through the use of cellular and molecular studies carried out on developing pouch young tissue. The capacity for generating an immunological response in adult and pouch young marsupials has been studied by following cellular proliferation in response to mitogens or mixed lymphocyte culture (MLC). After examining adult responses to mitogens and allogenic lymphocytes, optimised conditions were then used to examine the development of responsiveness in pouch young. Several further tests were conducted and findings shown. The study has shown that the earliest age at which Macropus eugenii is capable of mounting a T-cell mediated immune response is between 5 to 13 days post-partum / Doctor of Philosophy (PhD)
7

Regional biodiversity management strategy : case study on the Flinders Ranges /

Dorjgurhem, Batbold. January 1999 (has links) (PDF)
Thesis (M.App.Sc.) -- University of Adelaide, Dept. of Applied and Molecular Ecology, 2000. / Bibliography: leaves 107-117.
8

Reintroduction biology of yellow-footed rock wallabies (petrogale xanthopus celeris and P. x. xanthopus

Lapidge, Steven James January 2002 (has links)
Based on the recommendations of both the 1993 Reintroduction biology of Australasian Fauna Conference and the 1994 Rock Wallaby Symposium, captive-bred Yellow footed rock wallabies were reintroduced into areas of their former ranges in both South Australia and Queensland
9

Population modelling the yellow-footed rock-wallaby (Petrogale xanthopus xanthopus) in space and time /

Lethbridge, Mark. Unknown Date (has links)
Conservation biology is primarily concerned with the amelioration of species decline. The Yellow-footed Rock-wallaby (Petrogale xanthopus xanthopus) is a medium sized Macropod that inhabits the semiarid rangelands of South Australia and New South Wales. Its conservation status is Vulnerable C2a(i). In this study, population modelling, spatially explicit habitat modelling and Population Viability Analysis (PVA) have been used to better understand the factors that affect the abundance and distribution of the P. x. xanthopus in South Australia. The processes that drive the population dynamics of a species operate at different scales. As such this research involves a collection of several inter-related and scale-specific empirical studies that provide insights about the population dynamics of P. x. xanthopus. Each of these studies captures environmental, demographic and behavioural process acting on the population at different scales. These include the analysis of relative abundance data derived from an aerial census, mark recapture sampling of demographic parameters in relation to rainfall patterns and a collection of habitat models derived at different scales using presence-absence data. Spatially explicit PVAs enable the population dynamics of a species to be modelled in space and time. Using these data, a PVA is conducted to explore and rank the importance of the factors that threaten this species and help guide their future monitoring and management. Movement is also a key issue when considering problems such as isolation and inbreeding. Given that little is known about the dispersal behaviour of this species, a range of different dispersal behaviours are also simulated in the PVA using random and non-random mating algorithms, to estimate the potential for inbreeding. / Thesis (PhD)--University of South Australia, 2004.
10

Spatial modelling for the conservation of threatened species: distributions, habitats and landscape connectivity of the brush-tailed rock-wallaby (Petrogale penicillata).

Justine Murray Unknown Date (has links)
Ecological patterns and processes influence ecosystem function at scales from nanometres to global scales depending on the organisms involved. Predicting the presence and abundance of species, at scales appropriate to the organisms and the underlying processes, is central to ecology. Models of species’ distributions can provide important insights into pattern-process-scale relationships including the relative importance of various environmental factors and their interactions that influence habitat selection at the individual and population levels. Mapping current and potential distributions informs the conservation of threatened species by providing spatial information on where a species is likely to occur and the identification of habitat elements and their spatial configurations which influence occupancy and persistence. The aim of this thesis was to incorporate the principles of pattern, process and scale in the identification of habitat associations for threatened species within a species’ distribution modelling framework. Accurate modelling of species’ distributions depends on robust sampling designs, reliable data input and appropriate statistical methodologies that align with the ecological model. I applied a range of innovative statistical methods to various sources of data to identify important habitat associations for a threatened species at different scales and tested the discriminative ability of the resultant models. I integrated the results from extensive field sampling and expert elicitation to build connectivity networks using graph theory algorithms to identify important conservation priorities for threatened species. The threatened brush-tailed rock-wallaby (Petrogale penicillata) was chosen as a suitable study species for quantifying habitat relationships at multiple spatial scales using species’ distribution modelling. The distribution of brush-tailed rock-wallabies is restricted to a set of suitable habitat characteristics related to rocky terrain supporting cliffs and boulder piles that occur infrequently across a landscape. At the site scale, they require suitable resting and refuge sites provided by rocky habitats, while at a landscape scale their dispersal is dependent on the connectivity of suitable habitats. The species is listed as threatened throughout eastern Australia and endangered in some states. Information about its current distribution and occupancy status is essential to support habitat conservation and threat management. The first chapter provides a broad view of the literature on modelling of species’ distributions and the thesis aims and structure. In chapter 2, I assess the ecological scale relevant to habitat modelling for the brush-tailed rock-wallaby. In chapter 3 I test whether habitat models from one region can be extrapolated to neighbouring regions. I use a novel approach and elicitation tool in chapter 4 to collect expert knowledge and assess it with a comprehensive set of field data in a Bayesian framework. In chapter 5 I assess whether landscape connectivity is a determinant of site occupancy by using graph theory algorithms to identify important habitat patches and dispersal pathways for rock-wallaby movement in fragmented landscapes. The final chapter synthesises the individual chapters’ findings within the context of species’ distribution modelling. Management implications are discussed for the conservation of the brush-tailed rock-wallaby and its habitat network. Wider implications are also suggested for other rock-wallaby species and species living in similar environments. The results of the thesis showed the habitat of the brush-tailed rock-wallaby was affected by site-scale and landscape-scale factors, supporting the need for a multi-scale approach when investigating species-environment associations. I found that models performed well within a region at both scales. Extrapolating the models to neighbouring regions resulted in good predictive performance at the site scale but substantially poorer predictive performance at the landscape scale. When there is insufficient field data to build robust data models, management bodies would benefit from incorporating expert knowledge. The study demonstrates the potential errors in using experts with knowledge gained from outside the area of interest. Finally, I highlight the importance of accounting for the landscape connectivity between patches from the perspective of the individual animal. Least cost analysis, using graph theory algorithms, provides a cost-efficient and effective framework for identifying landscape connectivity patterns and key paths and patches to help inform suitable land management strategies for conservation of threatened species. There is much pressure from conservation and management agencies to produce models of species’ distributions that could be potentially be used in other regions or with similar species. The thesis combines ecological theory with rigorous statistical methodology to test different modelling techniques for species distribution modelling. It demonstrates how a combination of expert knowledge, extensive field data and landscape connectivity measures successfully predicts ecological relationships at a number of scales. Species’ distribution models can benefit from applying a robust sampling design and suitable modelling techniques to various data sources to generate ecologically-based information to improve our understanding of species-habitat associations and provide a reliable component to incorporate into conservation planning. This thesis therefore provides important advances to spatial ecology and ecological modelling of species distributions and management of threatened species.

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