Domestic cats that regularly catch wild animals still get most of their nutrition from food provided at home, research shows.

Scientists used forensic evidence from cats’ whiskers to see what regular hunters of wildlife had been eating.

The results showed that about 96% of their diet came from food provided by their owners, while 3% to 4% came from eating wild animals.

This suggests that predatory instinct, rather than hunger, is probably the main reason why some domestic cats regularly hunt wild prey.

“When food from owners is available, our study shows that cats rely almost entirely on this for nutrition,” Dr Martina Cecchetti, of the University of Exeter, said.

“Some owners may worry about restricting hunting because cats need nutrition from wild prey, but in fact, it seems even prolific hunters don’t actually eat much of the prey they catch.

“As predators, some cats may hunt instinctively even if they are not hungry – so-called ‘surplus killing’ – to capture and store prey to eat later.”

The researchers trimmed a whisker from each cat in the study, once at the start and once at the end.

Stable isotope ratios in the whiskers were then analysed, allowing the sources of protein from different wild and provisioned foods to be identified.

The team also tested the effects of different measures designed to prevent cats killing wild prey.

These measures included bells, Birdsbesafe collar covers, meat-rich diets, providing food using a puzzle feeder and regular play.

Based on analysis of their whiskers, cats with a Birdsbesafe collar cover consumed less wild prey, probably because they caught fewer birds.

“This study reassures owners of cats who hunt that the motive to hunt is instinctive, not driven by nutritional needs,” said Susan Morgan, chief executive of Songbird Survival, which sponsored the study.

“In the UK, we’ve lost half our songbirds in 50 years, but we can all help to stem this tide.”

Cats in the study were all regular hunters that had frequently and recently caught wild animals.

– The paper, Contributions Of Wild And Provisioned Foods To The Diets Of Domestic Cats That Depredate Wild Animals, is published in the journal Ecosphere.