Fourteen feral cats captured in the wild have been re-released to measure their predation on native animals.
The cats wear collars that track their whereabouts and activities through video, GPS and VHF beacons as part of the NESP TSR Hub’s Integrated management of feral herbivores and feral predators (Project 1.1).
The research, led by Dr Hugh McGregor from the University of Tasmania, seeks to understand how the hunting behaviour of feral cats changes post-calicivirus (when rabbit numbers suddenly fall), including by measuring the occurrence and impacts of pre-switching by cats.
There are long-term gains to native plants and animals resulting from the reduction in rabbit numbers through use of calicivirus (through improvements to vegetation as well as overall reductions in the densities of foxes and cats) but there may also be at least short-term detriment to some native animals.
“After calicivirus, the sudden scarcity of rabbit numbers could cause cats and foxes to ‘prey switch’ to native animals. In some circumstances, prey-switching could cause the local extirpation of a population of native species. For example, we think that the loss of some populations of rock-wallabies in the arid zone may have occurred because of prey-switching after the first calici virus release,” says Hugh.
Hugh aims to discover whether prey-switching occurs, and if so how it can be managed. He also aims to identify the threshold density of rabbits that results in cat densities with minimal impacts on native species.
“By describing the hunting behaviour, including the kill rates and prey choice of feral cats, we can make better calculations of the impacts of prey switching on native populations.
“We’ve been tracking the cats for a couple of months already, since July, and very early video footage is showing that the cats are hunting selectively around rabbit warrens and preferring rabbits as prey.
“When the footage shows a cat preying on a native animal, it can be quite confronting. The native animals are clearly unused to being hunted by such a predator.”
Image: feral farm cat, by Stavrolo
With other concerned conservation biologists, researchers from the Threatened Species Recovery Hub have developed a ‘blueprint’ for management responses to the 2019-20 wildfires. This report can be downloaded from our website.
The Threatened Species Recovery Hub of the National Environmental Science Program expresses our sympathy to everyone whose life has been impacted by these horrific fires, and acknowledges the heartbreak of families who have lost everything, including loved ones.
Many landscapes in Australia are fire-prone, and increasingly so. Altered fire regimes can have a serious negative impact on threatened plant species and ecological communities. A Threatened Species Recovery Hub project is working to better understand the effects of different fire regimes on threatened flora in order to improve fire management strategies and conservation outcomes.
Almost a quarter of Australia’s possums and gliders are listed as threatened under Australian environmental law, and many more are showing signs of decline. Dr Rochelle Steven from The University of Queensland believes people in the community can do a lot to support conservation, especially in urban areas.
The detection and monitoring of threatened species have been a strong area of research in the National Environmental Science Program and also the two national environmental research programs which preceded it. Hub Director Professor Brendan Wintle takes a look at what we’ve been achieving and why it is so important to the conservation of Australia’s threatened species.