The challenge for koala conservation on private land: koala habitat use varies with season on a fragmented rural landscape

Abstract

Land clearing for agriculture results in fragmented landscapes with diminished resources for wildlife. Habitat loss and fragmentation are widespread problems; however, their impacts are rarely assessed simultaneously at multiple spatial and temporal scales. We used a focal site, multiscale design to examine how landscape characteristics that affect the probability of koala Phascolarctos cinereus presence varies over multiple spatial and temporal scales in a fragmented rural landscape in north-western New South Wales, Australia. We modelled the effect of variables representing landscape characteristics at three spatial extents – transect, patch and site – over three seasonal periods (mid-spring, late-spring and midsummer). Koala activity level (as determined by faecal pellets) varied between surveys, and identifies short-term seasonal changes in habitat use. Koala presence had the strongest association with patch scale variables (habitat suitability, soil fertility and patch area). Temporal variation in the effect of tree and landscape characteristics on koala presence highlights the limitations of surveys at a single point in time, and emphasizes that further research is needed to advance our understanding of what drives temporal variation in koala habitat use at multiple spatial scales. Our results show that to arrest declining koala populations in rural agricultural landscapes, conservation and management plans must consider landscape scale processes over a variety of time scales, and engage stakeholders across multiple properties and tenures, to conserve both disturbed and suitable habitat on private land.