Rhinoceroses are arguably the most endangered of all large mammal taxa. In order for ongoing conservation of this species to be successful, it is crucial to accurately characterize the remaining genetic diversity for all rhinoceros species. To do this, I optimized a standard suite of 24 taxon-specific rhinoceros microsatellite loci. These loci have the power to provide the most comprehensive estimate of comparative microsatellite genetic diversity within and among the four extant African and Asian rhinoceros genera. These loci were further used to evaluate the comparative influences of rhinoceros species versus microsatellite taxonomic origin as predictors of rhino microsatellite diversity, and finally to examine the evolutionary relationships between extant rhino taxa. The African black michaeli rhino subspecies had the highest level of microsatellite genetic variability of all available rhinos, while southern white and Indian rhinos were the least variable rhinos. These findings also suggested that species and taxonomic origin of microsatellite loci were both significant predictors of microsatellite heterozygosity in rhinoceroses. A weak association between the Sumatran and black rhinos was found with a DLR neighbour-joining tree. The standard loci were able to assign unique genotypes to all available rhinos as well as differentiate between all rhino species by correctly assigning individual rhinos back to their respective populations. / Thesis (Master, Biology) -- Queen's University, 2008-07-02 23:01:32.553

Lake sturgeon, recently recommended to be listed as an endangered species under the Species at Risk Act, inhabit the various impoundments of the Winnipeg River system. Downstream passage through hydroelectric generating stations represents one of the major data gaps in our understanding of how hydroelectric development may be impacting lake sturgeon populations. Acoustic telemetry was used to investigate coarse-scale movements of juveniles, sub-adult and adults throughout the Slave Falls Reservoir, a 10 km long Winnipeg River impoundment, to assess patterns of downstream passage susceptibility and investigate fine-scale movements in the vicinity of the Slave Falls Generating Station. Movements of juveniles and sub-adults were generally restricted to areas of interconnected deep-water habitat, with movements through the shallow river narrows that sub-divide the Slave Falls Reservoir being rare. Adults did move through these narrows, albeit infrequently. Juveniles and sub-adults tagged in the lowermost section of the reservoir, as well as several adults tagged throughout the reservoir, were found to periodically utilize habitat immediately upstream of Slave Falls, where they would be susceptible to entrainment. Mean entrainment rates were estimated at 3.1% per year for adults tagged throughout the reservoir, and 17.9% per year for sub-adults tagged in the lowermost section of the reservoir. Fine-scale movement tracking revealed that three of eleven observed downstream passage events occurred via bottom-draw regulating gates, while another four events were also reasoned to have occurred via this route. The routes of the remaining four could not be determined. Eight of the eleven downstream passage events observed in this study were survived. While the survival of the remaining three fish could not be confirmed, it is highly likely that they also survived. Length-at-age analysis, supported by genetic methods, revealed that 23 of 151 (15.2%) of the lake sturgeon between 525 and 750 mm (fork length) captured in the 6 km stretch of river downstream of Slave Falls were fast-growing outliers, reasoned to have passed downstream through the Slave Falls Generating Station.

I investigated how orchid biology, floral morphology, and diversity of surrounding floral and pollinator communities affected reproductive success and hybridization of Cypripedium candidum and C. parviflorum. Floral dimensions, including pollinator exit routes were smallest in C. candidum, largest in C. parviflorum, with hybrids intermediate and overlapping with both. This pattern was mirrored in the number of insect visitors, fruit set, and seed set. Exit route size seemed to restrict potential pollinators to a subset of visiting insects, which is consistent with reports from other rewardless orchids. Overlap among orchid taxa in morphology, pollinators, flowering phenology, and spatial distribution, may affect the frequency and direction of pollen transfer and hybridization. The composition and abundance of co-flowering rewarding plants seems to be important for maintaining pollinators in orchid populations. Comparisons with orchid fruit set indicated that individual co-flowering species may be facilitators or competitors for pollinator attention, affecting orchid reproductive success.

Lake sturgeon, recently recommended to be listed as an endangered species under the Species at Risk Act, inhabit the various impoundments of the Winnipeg River system. Downstream passage through hydroelectric generating stations represents one of the major data gaps in our understanding of how hydroelectric development may be impacting lake sturgeon populations. Acoustic telemetry was used to investigate coarse-scale movements of juveniles, sub-adult and adults throughout the Slave Falls Reservoir, a 10 km long Winnipeg River impoundment, to assess patterns of downstream passage susceptibility and investigate fine-scale movements in the vicinity of the Slave Falls Generating Station. Movements of juveniles and sub-adults were generally restricted to areas of interconnected deep-water habitat, with movements through the shallow river narrows that sub-divide the Slave Falls Reservoir being rare. Adults did move through these narrows, albeit infrequently. Juveniles and sub-adults tagged in the lowermost section of the reservoir, as well as several adults tagged throughout the reservoir, were found to periodically utilize habitat immediately upstream of Slave Falls, where they would be susceptible to entrainment. Mean entrainment rates were estimated at 3.1% per year for adults tagged throughout the reservoir, and 17.9% per year for sub-adults tagged in the lowermost section of the reservoir. Fine-scale movement tracking revealed that three of eleven observed downstream passage events occurred via bottom-draw regulating gates, while another four events were also reasoned to have occurred via this route. The routes of the remaining four could not be determined. Eight of the eleven downstream passage events observed in this study were survived. While the survival of the remaining three fish could not be confirmed, it is highly likely that they also survived. Length-at-age analysis, supported by genetic methods, revealed that 23 of 151 (15.2%) of the lake sturgeon between 525 and 750 mm (fork length) captured in the 6 km stretch of river downstream of Slave Falls were fast-growing outliers, reasoned to have passed downstream through the Slave Falls Generating Station.

I investigated how orchid biology, floral morphology, and diversity of surrounding floral and pollinator communities affected reproductive success and hybridization of Cypripedium candidum and C. parviflorum. Floral dimensions, including pollinator exit routes were smallest in C. candidum, largest in C. parviflorum, with hybrids intermediate and overlapping with both. This pattern was mirrored in the number of insect visitors, fruit set, and seed set. Exit route size seemed to restrict potential pollinators to a subset of visiting insects, which is consistent with reports from other rewardless orchids. Overlap among orchid taxa in morphology, pollinators, flowering phenology, and spatial distribution, may affect the frequency and direction of pollen transfer and hybridization. The composition and abundance of co-flowering rewarding plants seems to be important for maintaining pollinators in orchid populations. Comparisons with orchid fruit set indicated that individual co-flowering species may be facilitators or competitors for pollinator attention, affecting orchid reproductive success.

Modeling species of conservation concern, such as those that are rare, declining, or have a conservation designation (e.g. endangered or threatened), remains an activity filled with uncertainty. Species that are of conservation concern often are found infrequently, in small sample sizes and spatially fragmented distributions, thereby making accurate enumeration difficult and traditional statistical approaches often invalid. For example, there are numerous debates in the ecological literature regarding methodological choices in conservation-based models, such as how to measure functional traits to account for ecosystem function, the impact of including rare species in biological assessments and whether species-specific dispersal can be measured using distance based functions. This thesis attempts to address issues in methodological choices in conservation-based models in two ways. In the first section of the thesis, the impacts of methodological choices on conservation-based models are examined across a broad selection of available approaches, from: measuring functional diversity; to conducting bio-assessments in community ecology; to assessing dispersal in metapopulation analyses. It is the goal of this section to establish the potential for methodological choices to impact conservation-based models, regardless of the scale, study-system or species involved. In the second section of this thesis, the use of consensus methods is developed as a potential tool for reducing uncertainty with methodological choices in conservation-based models. Two separate applications of consensus methods are highlighted, including how consensus methods can reduce uncertainty from choosing a modeling type or to identify when methodological choices may be a problem.

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.

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.