Document ID: chunk:federal_register_of_legislation:F2023L00432:reg:5:p2
Version: federal_register_of_legislation:F2023L00432
Segment Type: reg
Provision Reference: reg 5 (pt 2/8)
Character Range: 64115–66884

Foxes are established and more common in the southern part of the Greater Bilby's former range where they exerted more predation pressure than in the central and northern part of the Greater Bilby's range. An abundance of rabbits (Oryctolagus cuniculus) leads to elevated predator densities and consequential increased predation of bilbies and rabbits are largely restricted to the southern part of the Greater Bilby's current distribution (Southgate 1990a; Cox et al. 2013). The early spread and establishment of foxes was closely linked to the spread of rabbits (Saunders et al. 1995). Bilbies may have persisted in the most northern parts of its range because of fewer foxes (Vulpes vulpes) (Southgate et al. 2007).
It is not known whether the fox is continuing to expand its range north and west in the NT and WA, or whether expansion and contraction of the range of foxes is solely due to seasonal and climatic fluctuations (Saunders et al. 1995).
Feral cat predation is another major factor associated with the decline of bilbies. With less than 200 years of evolutionary exposure to feral cats, bilbies do not seem to have developed innate antipredator behaviours in response to the threat of feral cat predation (Steindler et al. 2018). The range of the feral cat overlaps with that of the current range of the Greater Bilby and has done for some time, so it is unlikely that the feral cats alone are responsible for the decline of the Greater Bilby across its range (Southgate 1990a).
At some locations and following particular seasonal conditions, feral cats can significantly limit and, at times, cause local extinction of bilbies. Predation by feral cats has been recorded at Dryandra (WA), Arid Recovery (SA), Matuwa/Kurrara Kurrara Indigenous Protected Area (ex Lorna Glen and Earaheedy pastoral leases) (WA) (Morris pers. comm., cited in Woinarski et al. 2014), Venus Bay (SA) and in the Tanami Desert (Tennant Creek and Kintore (NT)) (Paltridge 2002). Predation by feral cats can be severe in Qld (McRae pers. comm., cited in Woinarski et al. 2014) and requires ongoing feral cat control on Astrebla Downs and Diamantina National Parks (Qld) (Rich et al. 2014). Feral cats have led to the failure of bilby reintroductions outside fenced enclosures (Moseby et al. 2011) and within the enclosure at Currawinya National Park (Qld) when the perimeter fence deteriorated and feral cats entered the enclosure. At Arid Recovery (WA), bilbies exposed to low densities of feral cats over an extended period exhibited behavioural changes that increased their chance of survival (Ross et al. 2019). However, it is assumed that feral cat predation is likely at most locations, and along with fox predation may be the key impediments to reintroduction at many sites.