Critically Endangered Marsupial Calls Residential Gardens Home

Urbanization is one of the biggest global threats to biodiversity. However, urban areas can offer opportunities for biodiversity conservation because of the assortment of resources and numerous taxa that occur in these habitats. While the use of gardens by animals is well documented, the ability of native fauna to exclusively use (i.e. reside in) them is largely uninvestigated and therefore constrains our current understanding of their conservation 'value'. We aimed to determine whether individuals of a threatened species can exclusively reside in gardens for several months of their life, and the frequency that novel resources (i.e. non-natural) are used compared to natural ones. We predicted that individuals captured in gardens would use both bushland and residential habitat, and use natural resources more frequently than novel resources because of the assumption that remnant habitat is more suitable than modified gardens. Using the Critically Endangered western ringtail possum (Pseudocheirus occidentalis) as a case study, we captured 20 individuals in gardens and radio-tracked them for a period of 95 +/- 3.3 days to determine their habitat use. Contrary to our predictions, for the duration of our study individuals exclusively resided within gardens, irrespective of proximity to bushland, and used novel resources more frequently than natural resources for all behaviours. We also found that over half (53%) of all the captured female possums had pouch young, and at the conclusion of the study, male possums were on average 43 g heavier. Our results exemplify that gardens can be of sufficient quality to support individuals, and that these modified habitats should be incorporated into conservation policy in urban landscapes. Given the extensive number of threatened species located within cities globally, our finding that a threatened species can reside exclusively within gardens further highlights the conservation opportunity that residential landscapes and cities offer wildlife.