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Context. Post-release monitoring of rehabilitated koalas is lacking, meaning that the long-term success rate is unknown. Aims. We addressed the question: will a koala released from rehabilitation re-join the wild population and survive for months, if not years? Methods. Using ear tag records as unique identifiers of individual koalas, we sifted the 31-year set of 5051 koala admission records (1989-2020) of a koala rehabilitation group, Friends of the Koala, in Lismore, north-east New South Wales for records of koalas that had returned to rehabilitation for a second, third or fourth time. Key results. Of the 1771 koalas that were released, most (80%) had a coloured ear tag with a unique number. Of these koalas, 270 were admitted to rehabilitation two or more times and therefore represented an opportunity for post-release monitoring. Re-admission figures mostly fitted the pattern of first admissions, meaning that the released koalas had become part of the local koala population. Of the 270 koalas that were re-admitted into rehabilitation, 66% remained for more than 6 months in the wild, and 33% remained in the wild for more than 2 years. Conclusions. We conclude that rehabilitated and released koalas can survive in the wild long-term, even though some koalas were re-admitted after a very brief period post-release. Implications. The success of rehabilitation and release, as judged by re-admitted tagged koalas, is a more robust view of success for koala survival after rehabilitation than simply the proportion of released versus non-released koalas. [ABSTRACT FROM AUTHOR]

Context. The koala is a threatened species in New South Wales and long-term datasets of koala rehabilitation provide a valuable source of insight into local threats. Aims. To examine the longterm trends of the cause and fate of koalas admitted for rehabilitation to assist monitoring the recovery of koala populations and provide a new outlook on the limitations and strengths of rehabilitation records for koala conservation. Methods. We used data from long-term records (1989-2020) of the Friends of the Koala wildlife rehabilitation group in north-east New South Wales to identify spatial and temporal trends in 5051 koala admissions. Key results. Chlamydiosis was the most common cause of admission, affecting female koalas more often than males. Admissions of female koalas with chlamydiosis showed a two-fold increase over summer, and admissions for motor vehicle collisions and unsuitable environment increased in spring. The rescue locations of admissions show an increasing geographic spread over time, as well as an increasing density of records. Admission body scores were higher in koalas that were eventually released than in non-released koalas. Other main causes of admission were unsuitable environments, dog attacks, abandonment/orphaning and attacks from other species. Conclusions. We have produced an analysis and interpretation of a long-term dataset of the relative importance of various threats facing the koala population in north-east New South Wales. However, admissions to rehabilitation do not capture all the landscape-scale problems confronting koalas locally, particularly climate change and habitat loss. Implications. We have provided the baseline necessary to detect future changes in the causes for admission, rates of rehabilitation and post-release survival. [ABSTRACT FROM AUTHOR]