A multi-pronged campaign to control feral cat numbers is underway in Australia, with the commercial rollout of a new poison bait in coming months, the development of more sophisticated trapping devices, and the increasing use of dogs to both guard vulnerable native animal populations and to hunt down the felines.
Nocturnal and reclusive, the cats are difficult to count, but estimates range from between 5 million and 20 million wild felines roaming across the Australian continent. Europeans brought cats to Australia as domestic pets and mousers, and their descendants have proven adaptable to nearly every Australian environment. Feral cats thrive even in the desert regions where they do not need water to drink — slaking their thirst on the blood of their prey. Reproducing rapidly, with almost no predators, feral cats keep populating until there is no virtually prey left to kill.
Primarily responsible for at least 20 extinctions, including the desert bandicoot, the broad-faced potoroo and the crescent nailtail wallaby, cats have helped give Australia the dubious distinction of having by far the highest rate of mammal extinctions in the world.
Feral cats have wrought havoc elsewhere as well: In one recent report, scientists allege feral cats are at least partly responsible for 60 extinctions worldwide. But cats have perhaps wrought most havoc in Australia, the only continent, except Antarctica, with no native cats, and where the native wildlife has no instinctive dread of the feral menace. Weighing as much as 9 kilograms, cats have ripped a swathe through Australia’s wildlife and last year these descendants of the domestic cat, felis catus, were officially declared a pest by the federal government.
Gregory Andrews, Australia’s Threatened Species Commissioner, says the feral cat is a difficult species to deal with. A ferocious hunter, the cat prefers live prey, Andrews told the Nikkei Asian Review. It will only take a bait when prey is scarce — in winter, or in the dry season. “Different circumstances require different technology and different combinations,” he said “There’s no panacea.”
The federal government has invested more than $4 million into developing the Curiosity cat bait, a small meaty sausage encasing a hard-shell poison pellet. When Curiosity baits have been approved by the Australian Pesticides and Veterinary Medicines Authority, a decision expected later this year, commercial manufacture will begin. Andrews said that under the right circumstances Curiosity bait can reduce a feral cat population by as much as 80%.
Cats inhabit many remote and inaccessible districts in Australia, where it is difficult and expensive to send hunters and hunting dogs. Aerial baiting is considerably more cost-effective, although it works more efficiently with the fox, another introduced species.
The Western Australia government is already using a sausage cat bait called Eradicat, which, like the Curiosity baits, uses a sausage to attract the felines. Eradicat uses 1080 poison — a toxin tolerated by many Western Australia native animals. This tolerance prevents excessive collateral damage, when the baits are sampled by, say, goannas or the native quolls (a small carnivorous marsupial native to Australia). Curiosity uses a different tactic. Researchers have found that cats rip edible chunks from the bait and swallow them whole, making it more likely they will ingest the poison pellet.
Andrews and wildlife officials across Australia have other weapons in their arsenal. Dogs, specifically the Italian Maremma sheepdog, are being deployed in the southern state of Victoria to guard a tiny population of eastern barred bandicoot, now technically extinct in the wild.
Vociferous cat lobby
Further north, in the NSW Snowy Mountains, the endangered pygmy mountain possum is under the care of another couple of dogs — one to sniff out where the tiny creatures are living, the other to find the main predator, cats, which are then shot. Elsewhere, work continues on developing a trap that can detect the presence of a cat and squirt it with poison.
“Australians accept that it’s an unpleasant but necessary business to tackle feral cats, Andrews said. “I care about animal welfare. The RSPCA [Royal Society for the Prevention of Cruelty to Animals] backs what we’re doing 100 per cent.”
He says those opposed to baiting, a small but sometimes vociferous lobby comprising people who would prefer feral cats to be caught, neutered and then released, has had little real impact. “People saying I should be raped by feral cats; blown up by Isis; me and my family baited with 1080 and dumped in the bush,” he said. “But I sleep very well at night knowing that I’m saving our wildlife from extinction.”
Some of the more passionate cat-lovers have posted their comments on Facebook. “I was banned for ‘profanity’ and ‘abusive aggressive’ behaviour when I asked a genuine question about whether the long term effects of removing a large number of top level predators from the ecosystem had been studied,” one wrote in a Facebook post. “No profanity, just a question they couldn’t or didn’t want to answer.”
French film star Brigitte Bardot and British singer Morrissey have weighed into the debate. “The cats, who keep the rodent population under control, will be killed in a ferocious manner, using Compound 1080, which is a gut-wrenching poison of the most unimaginable and lengthy horror,” Morrissey said in a statement. “Your country is sullied by the blood of millions of innocent animals,” Bardot wrote in an open letter, “so please, don’t add cats to this morbid record.”
One solution could be biological control, which has been extensively used in Australia to keep the populations of introduced rabbits at manageable levels. If scientists developed a non-fatal disease that would render feral cats infertile, domestic cat breeders could be provided with a vaccine — with the result that the feral cat population would be painlessly eliminated within a matter of years. Cat breeders could be provided with a vaccine to ensure a supply of domestic felines for cat-lovers.
Andrews said the government is open to the idea of bio-control, but a note of caution has been sounded by some experts who fear such a disease could escape overseas and, in the worst case, even sterilise endangered native felines such as tigers in India or lions in Africa.
A feral cat with a phascogale, a carnivorous marsupial, in its mouth. Photo: Fredy Mercay, Australian National Environmental Research Program.