Bibliography: leaves 398-421. / xxxi, 421 leaves : ill. (chiefly col.), maps ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / The degree to which the conservation role of zoos can promote progressive environmental knowledge is debated. Generates data that zoo professionals can apply to future problem-solving and to increasing the relevance and effectiveness of zoo conservation policies for modern-day ecological problems. / Thesis (Ph.D.)--University of Adelaide, Mawson Graduate Centre for Environmental Studies, 1998

Habitat requirements and habitat use for Pseudophryne australis and Heleioporus australiacus were investigated to aid management of these threatened frogs around Sydney, Australia. Much of the work focussed on roads, commonly encountered features in the habitat of both species. The habitat requirements based on locality records of both frogs in the Sydney Basin were investigated at four spatial scales. Both species are habitat specialists. They showed a strong geological association with Hawkesbury Sandstone and occupy upper topographic areas with ephemeral watercourses of gentle gradients. Both frogs occur predominantly in areas of higher precipitation and milder temperature regimes compared to averages representative of the region. Leaf litter is an important feature of P. australis breeding sites, whereas H australiacus generally associate with crayfish burrows. Both species are dependent on natural vegetation with a complex structure. H australiacus have a relatively long larval period (3 - 12 months) and breed in ephemeral pools, exposing their tadpoles to the risk of dying due to early pond drying. In the laboratory, tadpoles responded to decreasing water levels by shortening their larval periods and metamorphosing earlier than siblings held at constant water level. Despite this plastic response, a number of pools in the field failed to produce metamorphs due to early drying, an observation also made on P. australis. Regular monitoring of breeding sites revealed increased reproductive success away from roads for both species probably because of relatively longer hydroperiods. Spatial distributions and associations with habitat features, and movement patterns of both frogs were further investigated using mark-recapture methods. Both species showed strong site fidelity. P. australis formed small aggregations and predominantly selected leaf litter piles despite their relatively low availability. Leaf litter piles in creeks moved over time and the animals moved with these piles. In contrast, H australiacus individuals formed no aggregations and showed no preference for any available structural vegetation type. Locations of individuals were independent of relative distances to creeks and artificial drains, but males appeared to be more common near culverts. However, individuals were randomly distributed in space and nearest-neighbour distances were high relative to individual movement distances, suggesting minimal overlap between relatively large home ranges. Radio-telemetry demonstrated that some H australiacus individuals burrow in the road environment. There they would be at risk of being dug up and possibly injured during road works. The results are discussed in relation to the spatial requirements of both species and the protection of utilised habitat features. Management options are suggested to mitigate the impacts of road works. Differences in spatial dynamics of both frogs with overlapping habitats highlighted in this study require species-specific management approaches.

Habitat requirements and habitat use for Pseudophryne australis and Heleioporus australiacus were investigated to aid management of these threatened frogs around Sydney, Australia. Much of the work focussed on roads, commonly encountered features in the habitat of both species. The habitat requirements based on locality records of both frogs in the Sydney Basin were investigated at four spatial scales. Both species are habitat specialists. They showed a strong geological association with Hawkesbury Sandstone and occupy upper topographic areas with ephemeral watercourses of gentle gradients. Both frogs occur predominantly in areas of higher precipitation and milder temperature regimes compared to averages representative of the region. Leaf litter is an important feature of P. australis breeding sites, whereas H australiacus generally associate with crayfish burrows. Both species are dependent on natural vegetation with a complex structure. H australiacus have a relatively long larval period (3 - 12 months) and breed in ephemeral pools, exposing their tadpoles to the risk of dying due to early pond drying. In the laboratory, tadpoles responded to decreasing water levels by shortening their larval periods and metamorphosing earlier than siblings held at constant water level. Despite this plastic response, a number of pools in the field failed to produce metamorphs due to early drying, an observation also made on P. australis. Regular monitoring of breeding sites revealed increased reproductive success away from roads for both species probably because of relatively longer hydroperiods. Spatial distributions and associations with habitat features, and movement patterns of both frogs were further investigated using mark-recapture methods. Both species showed strong site fidelity. P. australis formed small aggregations and predominantly selected leaf litter piles despite their relatively low availability. Leaf litter piles in creeks moved over time and the animals moved with these piles. In contrast, H australiacus individuals formed no aggregations and showed no preference for any available structural vegetation type. Locations of individuals were independent of relative distances to creeks and artificial drains, but males appeared to be more common near culverts. However, individuals were randomly distributed in space and nearest-neighbour distances were high relative to individual movement distances, suggesting minimal overlap between relatively large home ranges. Radio-telemetry demonstrated that some H australiacus individuals burrow in the road environment. There they would be at risk of being dug up and possibly injured during road works. The results are discussed in relation to the spatial requirements of both species and the protection of utilised habitat features. Management options are suggested to mitigate the impacts of road works. Differences in spatial dynamics of both frogs with overlapping habitats highlighted in this study require species-specific management approaches.

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on March 31, 2008) Includes bibliographical references.

Thesis (Ph.D.) -- McMaster University, 1998. / Includes bibliographical references (p. 223-258). Also available via World Wide Web.

Thesis (M.S.)--University of Missouri-Columbia, 2007. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on November 1, 2007) Includes bibliographical references.

Thesis (Ph. D.)--University of Nevada, Reno, 2007. / "December 2007." Includes bibliographical references. Online version available on the World Wide Web.

Thesis (Ph.D.)--University of Wollongong, 2006. / Typescript. Includes bibliographical references: leaf 124-146.

Thesis (M.F.A.)--Rochester Institute of Technology, 1993. / Typescript. Includes bibliographical references (leaf [37]).

Thesis (M.S.)--Michigan State University. Dept. of Fisheries and Wildlife, 2006. / Title from PDF t.p. (viewed on Nov. 20, 2008) Includes bibliographical references (p. 118-124). Also issued in print.