New state legislation that will potentially require owners to sterilise, microchip and register their feline friends might not be enough on its own to protect native small mammals, a new Murdoch University study has shown.
Dr Maggie Lilith’s research, funded by the City of Armadale, Western Australia, has found that protecting and restoring the habitats of declining native wildlife may be more important than simply controlling where pet cats can go.
She said the whole ecosystem had to be considered when looking for ways of protecting native fauna.
"While there are numerous studies on feral cats and their impacts on declining native fauna, the impact of pet cats on suburban wildlife or fauna in remnant bushland is relatively unknown although there is a wide perception of risk," Dr Lilith said.
"Our study in the City of Armadale showed no definitive evidence of predatory impacts from pet cats on small mammals.
"Mammal species diversity, richness and abundance were not significantly different between sites where cats were restricted."
She said despite the popular perception that cats were the main problem in conserving small mammals, vegetation appeared to be a more important issue.
"The species’ richness and abundance appeared linked to groundcover density in the various sites," Dr Lilith said.
"This factor, not cat restrictions, appeared to be the primary determinant of species’ richness, species’ diversity and absolute numbers of small mammals in these sites."
She said local residents were surveyed in regards to their attitudes and current cat husbandry practices.
The survey results showed a substantial proportion of respondents believed cat regulations were necessary – 75 per cent of owners and 95 per cent of non-owners.
Both owners and non-owners registered 70 per cent agreement or greater with the propositions that cats not owned by licensed breeders should be de-sexed, local councils should restrict the maximum number of cats that can be owned on one property and that pet cats entering nature reserves are harmful to wildlife.
Although fewer owners were prepared to keep their cats on their property at all times to protect wildlife, more than 80 per cent were willing to confine their cats at night if it was required.
"Owners seemed to be substantially motivated by the value of these measures in reducing injury to cats and facilitating the return of lost animals rather than concern over wildlife protection," Dr Lilith said.
"Community education on the values of cat confinement in regards to cat welfare might increase chances of compliance."
She said regulation of cats could be done at differing levels of intensity and cost, bearing in mind that the community is receptive to regulation of some aspects of cat ownership.
In 2008 Murdoch’s Biological Sciences postgraduate student Jacky Grayson completed a similar study in the City of Melville which showed the density of suburban housing and the lack of habitat were also more influential than the presence of cats in the lack of small passerines (perching and song birds), such as the Western Spinebill, New Holland Honeyeater and Rufous Whistler.
Currently only 18 of Western Australia's 139 local governments have cat control laws after Joondalup Council's proposed sterilisation local law was disallowed.
Further details about the proposed state cat legislation are available on the website www.dlg.wa.go.au.