Moseby, KatherineSchaefer, Rebecca Emma2024-09-242024-09-242024https://hdl.handle.net/2440/142551Introduction: Western quolls (Dasyurus geoffroii) were reintroduced to South Australia starting in 2014 at two sites - the Ikara-Flinders Ranges National Park (IFRNP), a large area where introduced predators are controlled through poison baiting, and Arid Recovery (AR), a fenced area that excludes introduced predators. Over 2020 – 2022 we collected data to conduct research to determine and compare the viability of the two populations. In chapter one we aimed to determine the population size, densities, rate of mortality, and current levels of genetic diversity of the two populations. Then, in chapter two we applied the results from chapter one to run two Population Viability analyses (PVA) one for each population. Chapter one: Barriers to sustainable populations include insufficient habitat, poor connectivity between quality habitats creating small, patch populations with low genetic flow, and an overabundance of introduced species. We aimed to determine what the specific barriers to each population’s viability were and how it was currently affecting the populations’ mortality rate and density. Through the Generalized Linear Mixed Model, we found quoll activity at IFRNP was highest in native pine woodlands, with a greater elevation if it was baited towards cats and foxes. Whilst at AR was in the dune habitats. Spatially Explicit Capture-Recapture analyses then determined that quoll density was higher at AR (0.01/ha) than at IFRNP (0.0007/ha). Finally, through radio-tracking and motion108 activated cameras found only a few individuals dispersing out of the protected areas Low-density estimates at each site suggest that both populations are not yet sustainable without further intervention to improve connectivity and reduce introduced predators. Future actions should also include monitoring outside the main protected areas to determine if females are expanding their territories or if it is just males in search of mates. Chapter two: PVAs are used to predict the probability that a population will go extinct within a certain time frame. With specific parameters collected from IFRNP and AR populations, we ran two separate PVAs to compare the qualitative probability of extinction of the western quolls within 100 years. Results from the IFRNP PVA found that scenarios with low juvenile mortality rates had a higher impact on the probability of extinction whilst high adult mortality did not (e.g. juvenile high = 81%, adult high = 20.4%). As well as scenarios with increased predator-controlled areas had the best chance of persisting for 100 years (e.g. 0.8%). In comparison, in AR there was very little difference between juvenile and adult mortality rates (e.g. juvenile high = 3.6%, adult high = 1%). Furthermore, even if scenarios had a low mortality rate the population would almost certainly go extinct (99 – 100%). This study demonstrates that different management styles have very different outcomes if not continued to be maintained in different ways. However, PVAs are to serve as just a guide and should not replace continuing monitoring to ensure management plans can be adjusted if necessary.enwestern quollpopulationviabilityreintroductionintroduced predatorsIkara-FlindersArid RecoveryThesis