Search

The continent of Antarctica has remained relatively free of the impacts of invasive species to date. However, Antarctica is under increasing anthropogenic pressure from human activity and climate change, elevating the risk of alien species introductions. Scientific research and the maintenance of research stations by Antarctic Treaty Parties requires the transfer of large amounts of equipment and cargo, which can harbour biosecurity risk material. Here, we assess two decades of data collected by the Australian Antarctic Division on the detection of biosecurity risk material in its facilities and vessels, both during transport and in Antarctica. We use these data to identify emerging risk species or pathways, to compare the variability in detections over time and to construct a consequence table to facilitate effective responses and resource allocation to future detections, translating our research findings into guidance for decision-makers. We find that, despite the development of policy instruments, monitoring and management for the prevention of alien species introductions to Antarctica, the risk of introductions is ongoing. We highlight areas of concern, including the transport of live spiders and the continuing potential for cargo to harbour biosecurity risk material and the benefit of ongoing training and investment and support for staff and expeditioners in the reporting of non-native species detections. Finally, we provide tools and recommendations for decision-makers and on-ground managers in the Antarctic biosecurity space, based on our research. Future studies on the establishment risk of commonly transported species would assist in improving these tools. [ABSTRACT FROM AUTHOR]

Dispersal behaviour and sociality are significant factors influencing survival at both the individual and population levels. In translocation and breeding programmes, social structure and sex‐biased philopatry and dispersal should be considered in order to maximise population viability and conservation outcomes. Here, we use the greater stick‐nest rat (Leporillus conditor), a native Australian rodent, as a case study to understand how knowledge of social structure and dispersal can inform conservation and translocation programmes. We combine high‐throughput DNA sequencing with field trapping data from a translocated population of greater stick‐nest rats at Arid Recovery Reserve, South Australia, to provide the first empirical evidence of female philopatry and male‐biased dispersal in this species. Males were found to disperse, on average, 1.5 km from the natal nest, while females typically did not disperse beyond 500 m. Further, recapture data showed that females demonstrated a higher degree of nest fidelity than males over time. Based on these findings, we make two key recommendations for future translocations of the species. Firstly, founders should be harvested in small groups at adjacent nest sites with groups separated by a minimum of 1.5 km allowing family group structure to be retained during translocation while simultaneously maximising genetic diversity. Secondly, translocated individuals should be released in family cohorts into patches of optimal habitat that contain adequate shelter substrates interspersed over short distances (~300–500 m, the maximum dispersal distance of females found in this study), thereby facilitating nest establishment and maintenance of family groups. The results of this study have implications for conservation and reintroduction biology as a whole; we highlight the importance of considering spatial genetic structure during all stages of translocations to improve outcomes, and the value of combining genetic and field data to better understand species' social and spatial preferences. [ABSTRACT FROM AUTHOR]