Evidence for a recent decline in the distribution and abundance of the New Holland mouse (Pseudomys novaehollandiae) in Tasmania, Australia

The New Holland mouse (Pseudomys novaehollandiae) was recognised to be at threat of extinction at an International, National, and Tasmanian State level in 2008, 2010, and 1995, respectively. The species inhabits the floristically diverse dry heathlands and associated vegetation communities that typically arise from mosaic burns. In this regard the New Holland mouse could be considered a flagship species for healthy heathlands. We present 18 years of search and capture records collected since 1998 from Tasmania to show that there has been a contraction over the last nine years from 16 to 2 in the number of sites from which the species has been detected, and more than a 99% reduction in capture-per-unit-effort. These results raise concern as to the viability of the species in Tasmania. Strength of inference regarding the magnitude and causes of decline in distribution and abundance would be improved by regular and systematic monitoring. The considerable overlap between the potential causes of the New Holland mouse's decline in Tasmania and regional declines in mammal assemblages nationally, suggest that recovery efforts for the New Holland mouse could have positive outcomes for all species inhabiting lowland dry heathlands in Australia.