Rabbit warrens: an important resource for invasive alien species in semi-arid Australia

Context The decline and extinction of native burrowing mammals across much of Australia has resulted in a loss of underground refugia constructed by native fauna in the environment. The introduced European rabbit (Oryctolagus cuniculus) is now the most widespread mammalian burrower across Australia. Rabbits are an invasive species in Australia, and the destruction of rabbit warrens for pest management is common practice. This destruction of warrens removes a potential refuge for both rabbits and other species in the environment. In landscapes where critical weight range burrowing mammals have declined, the widespread destruction of rabbit warrens removes many underground refuges for several commensal animal species. Aims To identify the use of rabbit warrens by fauna in the seasonally hot, semi-arid Ikara-Flinders Ranges National Park (IFRNP) in South Australia. Methods We used camera traps placed at burrow entrances of warrens and nearby structure to identify the vertebrate species that interact with rabbit warrens in the IFRNP. Key results We recorded 11 bird, nine mammal and eight reptile species present at the entrances of rabbit warrens. Only four of the taxa recorded on cameras in our study showed a preference for warrens over adjacent above-ground structure, three of them introduced species. The alien commensal species recorded using the burrows were rabbits, house mice (Mus musculus) and feral cats (Felis catus). Conclusions Rabbit warrens in the IFRNP are an important resource for a range of native and alien commensal species. In our study, they seem to be of special importance for introduced species. Implications Warren removal in the IFRNP may negatively impact native commensal species in treated areas but is likely to be of long-term net benefit for a wider range of native animals.