AbstractInternational biodiversity conservation efforts are urgently needed to halt or reverse the population declines of threatened species. Although there is potential for substantial positive contributions by zoos and public aquaria, tangible conservation successes are rarely demonstrated, in part due to a lack of clear and defensible evaluation methods. To address this methodology gap, this thesis used a case study of the largetooth sawfish (Pristis pristis) to demonstrate new conceptual models and methodological approaches to: prioritise species for conservation contribution evaluation; select appropriate indicators of conservation success; and evaluate the success of P. pristis releases from a public aquarium, public education, research, and conservation activities.
The survival and movements of released P. pristis were compared to wild individuals using acoustic telemetry. While captivity affected behaviours, aquarium sawfish had similar diel activity and habitat use patterns, and lower mortality, than wild sawfish. If P. pristis are to be harvested for aquaria, optimal conservation outcomes could be achieved by targeting individuals in the first year of life when natural mortality is highest, with releases into the freshwater reaches of the natal river before they reach ~2800 mm total length.
Education, research, and conservation activities associated with P. pristis displays at four Australian aquaria were found to be unlikely to contribute substantially to sawfish conservation. Adaptive management strategies to improve conservation outcomes were identified, including targeted exhibit interpretation, more specific conservation goals, and increased support for research and conservation projects.
The approaches developed and demonstrated in this thesis effectively identified changes to management and policy strategies that may improve biodiversity conservation outcomes. They can be applied to captive wildlife displays globally, facilitating more frequent and rigorous formative and ongoing evaluations. Repeated evaluations can quantify changes to conservation success after implementing adaptive management strategies, thus allowing zoos and aquaria to truly validate their conservation commitments.
|Date of Award||21 May 2021|
|Supervisor||Peter M. Kyne (Supervisor) & David Crook (Supervisor)|