source : the age
February 20, 2026 — 3:30pm
In Australia, it is illegal to own a pet tortoise. It is illegal to import an exotic bird. It is illegal to buy foreign Sea-Monkey eggs with your Sea-Monkey aquarium.
And yet, you can import your cat. You can phone up a cat breeder and buy one. You can keep your cat in your garden and let it roam the neighbourhood. I saw one on my street yesterday, a corpulent thing, slinking between cars, no doubt fattened mightily with the corpses of my local birds, mammals and even insects. This is insanity. It is an environmental catastrophe.
I am a zoologist. I love animals. I have even known a cat or two that I liked very much. But I’m also an evolutionary biologist. Cats kill more of Australia’s native species than any other exotic import. It’s time we outlawed pet cats, just as we outlaw other exotic animals inappropriate to the Australian environment.
Last month, there was a little dust-up in the scientific community over the role of domestic and feral cats in Australian mammal extinctions. A paper in late 2025 that had tried to cast doubt on cats’ role in the devastation was piecemeal dismantled by a 25-strong group of conservation scientists and the Biodiversity Council. The invasive predators are indeed still on the hook for the carnage – and not just of some species.
“The evidence is overwhelming; cats and foxes were the primary driver of the decline of most of the Australian mammals that have become extinct since 1788, and continue to drive the decline of many remaining species,” said Professor John Woinarski, who led the study.
The cats do not limit themselves to mammals, of course. They are famously bad for birds. In New Zealand, several iconic species survive only on mammal-free offshore islands because cats and other introduced mammals have made survival impossible on the mainland.
These introduced hunters are simply not part of the evolutionary history of the wildlife of this continent, and their presence here is an ongoing disaster for our native wildlife.
Shall I put some numbers on it? For context, let’s think about chickens. Chickens are not wild animals, but just for argument’s sake, how many do Australians kill per year? Just over 700 million. A lot of animals die by our hands, deliberately or otherwise. The cats? Between feral and pet cats, they kill 3 billion wild animals a year. Or 8.2 million a day. The Invasive Species Council breaks down the daily toll: “On average, cats kill 2.92 million mammals, 1.67 million reptiles, 1.09 million birds, 0.26 million frogs and 2.97 million invertebrates every 24 hours.”
Leaving out the feral cats, just the pets are estimated to kill almost 200 animals per cat, per year, mostly native species. And every pet cat is a potential escapee, tomorrow’s feral Tom. Your cat is a killer, and it cannot be permitted to live here.
There is no excuse for the cavalier way we treat cat ownership, especially against the strict quarantine regulations in place against other potential threats to our unique and precarious wildlife. It is rightly illegal to own or import a fox – and yet we have a regulated industry for the breeding and selling of cats, which do about 10 times more damage. We are allowing a massacre to persist for the sake of keeping a discretionary pet. We do not need cats. We need to be without them.
We need to make it illegal to own a cat in this country. They are not a suitable pet for our environment. We can do it gradually and compassionately: current pet cats can be kept if spayed or neutered, and kept exclusively indoors until their natural deaths, under severe legal penalty for violation. The breeding trade should be shut down, with due support for those in the industry to transition to other ventures. Over time, the pet cats will slowly become extinct, so that some of our native wildlife might not.
“Indoor cat” owners will object. They are responsible, they’ll say. They are conservation-minded. And they may well be – but their pets are part of a society-wide practice that is neither containable nor sustainable. As long as pet cats exist, some will get outside and cause mayhem. They can keep their pets indoors until their pets pass on, but then, no replacements.
The feral cat problem also needs to be tackled, and is trickier. Foxes too. You have to find them, after all. But that is no excuse for dragging our feet on eliminating pet cats, which is far more straightforward and would reduce the total number of cats on the continent by 40 to 80 per cent.
As I said, I love animals. I would love to have a pet tortoise, but I accept that sacrifice for the protection of the Australian ecosystem. Cat lovers need to do the same.
Please keep your hate mail brief and civil.
Antone Martinho-Truswell is a Sydney-based author, zoologist and evolutionary biologist. He is a research affiliate of the School of Life and Environmental Sciences at the University of Sydney.
Antone Martinho-Truswell is a zoologist and evolutionary biologist. He is a research affiliate of the University of Sydney, and dean of Graduate House at St Paul’s College.
