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Context: Toxic meat baits are the most effective broadscale method used for reducing the densities and impacts of feral cats (Felis catus) on vulnerable Australian native fauna when alternative prey is minimal. Aims: Our aim was to assess the efficiency (proportion of baits removed by target animals) and effectiveness (proportion of target animals removed) of Eradicat ® baits and to identify how their use may be improved in Southern Jarrah Forest ecosystems of Western Australia. We sought to determine how, when, and where best to deploy baits using the current Eradicat ® bait prescriptions to maximise the reduction of feral cats. Methods: Eradicat ® uptake trials were conducted over a 15-month period using remote sensor cameras (RSCs) to observe animals interacting with the baits at 40 sites. Ten successive baiting trials were conducted, each involving four randomly selected sites (two replicates for each of two bait deployment methods: clusters and transects). Key results: The fate of 5658 Eradicat® baits at 2000 bait locations was recorded during 54,361 camera trap nights. Despite occupancy rates being high for cat and fox (Vulpes vulpes), (92% and 84%, respectively), the efficiency and effectiveness of Eradicat ® baits was low for both introduced predators (cat: 0.1% and 10–12%, respectively; and fox: <0.6% and 8–20%, respectively). There were no major differences in baiting efficiency in relation to bait deployment method or time of year. More than half (56–58%) of the baits were removed by non-target animals prior to an introduced predator being observed on camera at the bait location. Along transects, there were more cat and fox visits closer to tracks and surface water features. Foxes were also more likely to visit bait locations closer to private property. Younger cats appeared to be more interested and more likely to eat a bait than older cats. Conclusions: Substantial improvements could be made by increasing bait availability (reducing non-target interference), detectability and attractiveness to cats. Implications: Additional introduced predator threat abatement methods may be needed for the conservation and recovery of many threatened native mammals in the Southern Jarrah Forests and elsewhere in Australia. Feral cat baiting should be conducted within an integrated and holistic invasive animal management system. Improving the management of feral cats is paramount for the conservation and recovery of many threatened Australian mammals. This study found that the efficiency and effectiveness of Eradicat ® baits in the Southern Jarrah Forests of Western Australia were low. We provide recommendations for improvements within an integrated and holistic invasive animal management framework to deliver better biodiversity conservation outcomes. Photograph by Marika Maxwell/DBCA. [ABSTRACT FROM AUTHOR]

Context: Predator free havens are increasingly relied upon to preserve populations of imperilled species, yet despite their substantial cost, the success of these ventures is rarely critically evaluated. Aims: Based on 12 years of population monitoring data, we report on the translocation of woylies (Bettongia penicillata ogilbyi) to Perup Sanctuary, a 423 ha predator-free haven in the south west of Western Australia. Methods: We built spatially explicit capture–recapture models to estimate population density, population growth rates, and survivorship of woylies inside the sanctuary. Using these estimates, and additional demographic information, we aimed to show key drivers of population density, evaluate the establishment of the sanctuary population against predetermined translocation success criteria, and run simulations of different sampling designs to determine a robust sampling design for future monitoring of this population. Key results: The population rapidly increased in the first 3 years (2010–2013), and then fluctuated around a density of ~0.9 woylies ha−1 before declining slightly in recent years to ~0.6 woylies ha−1. All translocation success criteria evaluated were met. The previous 3 months' rainfall was a key driver of population density and body weight declined over time, indicating that the population may be regulated by food resources. Conclusions: Woylies have established and persisted in Perup Sanctuary, and against the criteria, the translocation of woylies into Perup sanctuary is a success. Harvests from this population appear to have been sustainable. We discuss these findings in the context of the Perup Sanctuary, and recommend ongoing monitoring continue to ensure that the population remains viable and well managed. Implications: We describe important considerations for the supplementation and harvest of fenced populations, including: the source of animals (selecting free-living individuals over captive ones); the timing of release (releasing more individuals early on may improve establishment probabilities); and rates of harvest (<30% of adults harvested per generation seemeded to be sustainable for woylies in this case). The results from this study can inform the ongoing management of this and other havened populations, to ensure they continue to benefit mammal conservation. In response to predation from introduced predators, imperilled Australian mammals are increasingly preserved in predator-free havens, yet detailed monitoring of such populations is rarely reported. This study describes the establishment of Endangered woylies in a predator-free sanctuary in Tone–Perup Nature Reserve, Western Australia, revealing estimates of the growth and health of the population. Recommendations are made for the strategic management of this and other havened populations to improve conservation outcomes. Photograph by Natasha Harrison. [ABSTRACT FROM AUTHOR]

Context: Invasive predators are major drivers of global biodiversity loss. Red foxes (Vulpes vulpes) and feral cats (Felis catus) have contributed to the decline and extinction of many native species in Australia. The deployment of poison baits to control fox populations is a widespread conservation tool, but the effects of baiting intensity, rainfall and prey abundance on baiting effectiveness remain poorly understood. Aims: We aimed to understand what influences the association between fox baiting intensity, red fox activity and feral cat activity, to provide inferences about what might affect the effectiveness of fox baiting in reducing fox activity. Methods: We used generalised linear models to assess how fox and cat activity changes in relation to fox baiting intensity, rainfall, native prey availability and distance to agricultural land over a 6-year period (2006–13) in the forest ecosystems of the Upper Warren region of south-western Australia. Key results: We found that fox activity was negatively associated with rainfall in the previous 12 months and positively associated with prey abundance and fox baiting intensity. We also found an interaction between fox baiting and prey abundance, with fox activity increasing with prey activity in areas of low and moderate baiting intensity, but remaining constant in areas of high baiting intensity. Feral cat activity was positively associated with prey abundance and fox baiting intensity. We found no clear relationship between fox and cat activity. Conclusions: The drivers of the association between fox baiting and fox activity are unclear because intense fox baiting was targeted at areas of known high fox abundance. However, our results indicate that intense fox baiting may be effective at decoupling the positive association between fox activity and prey abundance. Our results also suggest a positive association between fox baiting intensity and feral cat activity, thus supporting the case for integrated fox and cat management. Implications: We caution interpretation of our results, but note that management of invasive predators could be improved by adjusting the intensity of management in response to changes in environmental conditions and local context (e.g. strategically conducting intense predator management where prey abundance is highest). Improved understanding of these associations requires a monitoring program with sufficient replication and statistical power to detect any treatment effects. Invasive predators are major drivers of global biodiversity loss. Red foxes (Vulpes vulpes) and feral cats (Felis catus) have contributed to the decline and extinction of many native species in Australia. We aimed to understand what influences the association between fox baiting intensity, red fox activity and feral cat activity. Although the association between fox baiting and fox activity is unclear, our results indicate that fox baiting may be most effective at decoupling the positive association between fox activity and prey activity. Our results also suggest a positive association between fox baiting intensity and feral cat activity, meaning integrated fox and cat management is required in the Upper Warren. Image created by the authors. [ABSTRACT FROM AUTHOR]

The woylie Bettongia penicillata is categorized as Critically Endangered, having declined by c. 90% between 1999 and 2006. The decline continues and the cause is not fully understood. Within a decline diagnosis framework we characterized the nature of the decline and identified potential causes, with a focus on the species’ largest populations, located in south-west Western Australia. We described the spatio-temporal pattern of the decline, and several attributes that are common across sites. We categorized the potential causes of the decline as resources, predators, disease and direct human interference. Based on the available evidence the leading hypothesis is that disease may be making woylies more vulnerable to predation but this remains to be tested. No substantial recoveries have been sustained to date, and one of the three remaining indigenous populations now appears to be extinct. Therefore, verifying the factors causing the decline and those limiting recovery is becoming increasingly urgent. Active adaptive management can be used to test putative agents, such as introduced predators. Insurance populations and ecological monitoring should also be included in an integrated conservation and management strategy for the species. [ABSTRACT FROM AUTHOR]