Chaser of laser pens, vanquisher of cucumbers, and overall champion of the Internet, cats are beloved by many. But your kitty may be hiding a dark secret, and no, we’re not talking about the parasite that can infect you and might make you go crazy. Cats – spread around the globe by their two-legged slaves – have been responsible for at least 63 extinctions of mammals, birds, and reptiles.
In what is thought to be the most comprehensive review of extinctions caused by invasive predators, researchers have found that at least 87 birds, 45 mammals, and 10 reptiles have been driven off the planet thanks to the introduction of predatory mammals. Out of all those considered, rodents have actually caused the most damage, followed by those pesky pussies, and then red foxes, dogs, pigs, and the Indian mongoose.
It has long been known that when we traversed the planet, we took with us a whole menagerie of creatures that have wreaked damage to the local wildlife wherever we stopped off. From the dodo in Mauritius to the pig-footed bandicoot in Australia, many species were well known to have been driven over the edge because of these introductions. But the exact scale of this catastrophe has remained elusive as no one had compiled it all together, until now.
“Our research shows that in parts of the world, invasive mammalian predators are major drivers of species decline and extinction,” explains co-author Dr Tim Doherty, from Deakin’s Centre for Integrative Ecology, in a statement. The study is published in PNAS.
By looking at huge database of references and trawling the IUCN’s Red List of Threatened Species, Doherty found that invasive mammals contributed to an “astonishing” 58 percent of all bird, mammal, and reptile species extinctions known to have occurred in the last 500 years.
“We also found that a further 596 threatened vertebrate species have suffered negative impacts from a total of 30 invasive predator species,” Doherty added.
Those creatures most at risk tend to be endemic island animals, as documented by the widespread extinctions experienced in Madagascar and New Zealand. Stephens Island wren is a perfect example, as the entire species of bird is thought to have been wiped out within a matter of years of people – and their cats – arriving on the remote island off the coast of New Zealand. Only ever identified by the carcasses carried back by many a cat, and not as is widely reported by a single feline named Tibbles, by the time the wren was recognized as a new species, it was already gone.
Nowadays, conservationists are a little more switched on when it comes to protecting native habitats against invasive mammals. The New Zealand government, for example, has announced ambitious plans to eradicate all invasive mammalian predators, including feral cats, by 2050, and the researchers of this latest study hope that their work might inspire more nations to follow suit.