Contraction in the range of Malleefowl (Leipoa ocellata) in Western Australia: a comparative assessment using presence-only and presence—absence datasets

Abstract

As human impacts on habitat increase in their intensity and scale it is increasingly important that we are able to characterise and monitor changes in the distribution of threatened species. The Malleefowl (Leipoa ocellata) is listed as vulnerable in Australia and the National Recovery Plan suggests that its range has contracted by 45% in Western Australia (WA). We quantified changes in the range of Malleefowl in WA and determined the relative influence that various threatening processes, such as land clearing and agricultural development, may have had on its range. We also investigated whether presence-only data (from existing survey and reporting) could reliably assess the status of Malleefowl by comparing presence-only data with presence-absence data. To obtain a presence-absence dataset we interviewed long- term residents within our study area of 64000 km² about the occurrence of Malleefowl. The range of Malleefowl has contracted in WA but this contraction is less substantial than previously claimed. The contraction in range within the agricultural landscapes of south-western WA is associated with the extent of land clearing, the number of years since commencement of agricultural activity, and the number of sheep within a landscape. To conserve Malleefowl, we believe landscapes developed for agriculture in recent decades must be protected to ensure they do not develop attributes found in landscapes that have been heavily cleared and occupied since the early 1900s.