Cats kill millions of animals every year and should be kept indoors, scientists say

Rob Waugh
Contributor
Cats kill millions of smaller animals (Getty)

Pet cats take a staggering toll on local wildlife, killing up to 230 million native animals in Australia each year, a study has found.

Researchers behind the project have said that pet cats are “a problem” and advised that they should be kept indoors.

On average, each pet cat killed 186 reptiles, birds and mammals per year, ScienceAlert reported.

The researchers found that while pet cats kill 25% less than feral cats, the animals live at much higher densities, so the predation rate per square kilometre from pet cats is 28-52 times higher.

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Dr Sarah Legge, professor at the University of Queensland, told The Guardian: “If we want native wildlife in our towns and cities – rather than introduced rodents and birds – then there are choices to be made.

“All we need to do is keep pet cats contained.

“If we accept that feral cats in the bush are a problem, then we have to accept that pet cats in town are also a problem.”

In the UK, the Mammal Society estimates that cats kill up to 100 million prey items every spring and summer, of which 27 million are birds.

The most commonly caught birds are house sparrows, blue tits, blackbirds and starlings.

But Britain’s RSPB says there’s no evidence that the animals are responsible for declines in bird numbers in the UK.

Read more: Cats ‘spread the virus to other felines’

Many pet owners believe that their cats don’t kill animals, but research has shown that many cats don’t bring home all of their prey. 

Studies using video collars found that cats bring home only 15% of their kills, Science Alert reported

The findings were based on a review of 66 studies on predation by pet cats worldwide, including 24 Australian studies.

The researchers wrote: “Pet cats kill introduced species more often than do feral cats living in natural environments, but, nonetheless, the toll of native animals killed per square kilometre by pet cats in residential areas is still much higher than the toll per square kilometre by feral cats.”

“The high predation toll of pet cats in residential areas, the documented examples of declines and extirpations in populations of native species caused by pet cats, and potential pathways for other, indirect effects (e.g. from disease, landscapes of fear, ecological footprints), and the context of extraordinary impacts from feral cats on Australian fauna, together support a default position that pet cat impacts are serious and should be reduced.”