Habitat preference for fire scars by feral cats in Cape York Peninsula, Australia

Abstract

Context Feral cats are implicated in the decline of terrestrial native mammals across northern Australia. Research in the Kimberley region of north-western Australia found feral cats strongly selected for fire scars when hunting, suggesting that intensifying fire regimes will have severe consequences for declining prey species. Aims We tested the generality of cat–fire interaction beyond the Kimberley, by measuring habitat selection of feral cats in relation to fire scars and habitat types in north-eastern Australia. Methods Our study was conducted at Piccaninny Plains Wildlife Sanctuary, Cape York Peninsula. We live-captured feral cats during the dry season of 2015, released them with GPS collars set to record fixes at 15-min intervals, and recaptured cats 4 months later. We created dynamic habitat maps of vegetation types, fire and wetlands, and compared cat habitat selection using discrete choice modelling. We also measured cat density from arrays of camera traps and examined cat diet by analysis of stomach contents. Key results We obtained GPS movement data from 15 feral cats. Feral cats selected strongly for recent fire scars (1 or 2 months old), but avoided fire scars 3 months old or older. Three long-distance movements were recorded, all directed towards recent fire scars. Cats also selected for open wetlands, and avoided rainforests. Density of cats at Piccaninny Plains was higher than recorded elsewhere in northern Australia. All major vertebrate groups were represented in cat diet. Conclusions We showed that feral cats in north-eastern Australia strongly select for recent fire scars and open wetlands. These results are consistent with those from the Kimberley. Together, these studies have shown that amplified predation facilitated by loss of cover is likely to be a fundamental factor driving mammal decline across northern Australia. Implications Reducing the frequency of intense fires may indirectly reduce the impact of feral cats at a landscape scale in northern Australia. We also suggest that managers target direct cat control towards open wetlands and recently burnt areas, which cats are known to favour.

Peak hour in the bush: linear anthropogenic clearings funnel predator and prey species

“…The impact of landscape level disturbances, such as fire, on feral cats, has recently been brought to light (McGregor et al . , ). Similarly, understanding the effects of clearing on feral cats, and the native species that they threaten, is key to informing management strategies.…”

Ecology and Conservation of a New Carnivorous Marsupial Species: the Silver-Headed Antechinus (Antechinus argentus)

“…The present study corroborates other recent work that recommends burning regimes that retain vegetation for habitat and important refuge for small mammals from introduced predators (McGregor et al, 2014, Legge et al, 2011b, Leahy et al, 2016, Andersen et al, 2012, McGregor et al, 2017.…”

“…In particular, feral cats (Felis catus) have been shown to travel large distances to reach recently burnt habitat, amplifying predation on exposed native species in the absence of sufficient cover (Dickman, 1996, McGregor et al, 2014, McGregor et al, 2017. Recent evidence has linked the declines of small mammal species with these amplified feral predation effects due to fire, as well as the effects of grazing by introduced herbivores (Legge et al, 2011a While the approach of the present study emphasised vegetation composition, we suggest that future research focus on structural habitat elements such as the size and shape of vegetation, for example the diameter and leaf density of grasstree crowns.…”

Location of long‐term communal burrows of a threatened arid‐zone lizard in relation to soil and vegetation

“…In north‐eastern Australia, feral cats were found to selectively hunt in fire scars in the very immediate (1–2 month) post‐fire period (McGregor et al . ). Attraction of predators to an area that has just been burnt may promote high levels of predation, whereas more subtle and persistent differences in cover between burrow sites may have a relatively negligible impact.…”