Killer kitties: cats are eating 2,000 species, including hundreds that are at risk | Cats

Cats may be adored human companions, but they’re also extremely efficient killers, according to a study that shows they eat more than 2,000 species worldwide — including hundreds of conservation concern.

Since domestication 9,000 years ago, domestic cats have spread to all continents except Antarctica. In the paperpublished in Nature Communications, researchers describe them as “some of the most problematic invasive species in the world”.

“Our study sheds light on the predatory habits of one of the world’s most successful and widespread invasive predators,” the researchers, led by Christopher Lepczyk of Auburn University in the US, wrote in the paper.

Birds, mammals, insects and reptiles are all on the menu, 17% of which are of conservation concern according to the research, which is the first to quantify their diet on a global scale.

In total, cats eat 981 species of birds, 463 reptiles and 431 mammals – accounting for around 90% of the species consumed. They have also been found to feed on 119 species of insects and 57 amphibians.

Cats are particularly harmful on islands, where they eat three times the number of conservation species compared to what they eat on continents. For example, they are known to have eaten species now extinct in the wild, including New Zealand’s Stephens Island Rockwren and the New Zealand quail.

Their impact on wildlife has prompted heated debate in New Zealand, where one is a politician campaigns to eradicate them completelyand controversy erupted over contests encouraging children to shoot wild cats.

In Australia alone, cats are estimated to kill more than 300 million animals every year, with conservation groups calling for cats to be kept indoors. Some places have implemented cat exclusions. In the southwestern German town of Walldorf, people were ordered to cats locked inside for three months in the spring to protect an endangered population of crested lapwings, which breed at that time.

Previous research found there is a “significant blind spot” when it comes to addressing the “large-scale negative impacts” of domestic cats on native wildlife.

The study found that about 9% of known birds, 6% of known mammals, and 4% of known reptile species are eaten by cats – and they are not picky snackers. “Cats largely eat what’s present,” researchers wrote. “If a species is missing from the diet analysis, it is likely that the prey is either absent or rare in the surrounding environment.”

The scientists arrived at these figures by searching hundreds of existing studies. They believe their final estimates are conservative, and will grow as more research is done. Their study looked at free-ranging domestic cats. Some of the larger animals included in the total count may be caught by cats, which are not necessarily caught as prey.

A spokesperson for the Royal Society for the Protection of Birds (RSPB) said: “Fitting bells with quick-release collars and keeping cats inside overnight are simple ways to reduce the number of wild birds and other wildlife they catch. , to reduce. Ultrasonic devices can also be a harmless but effective way to reduce the amount of time cats spend in gardens.

“Apart from gardens, cat predation can cause particular problems for vulnerable and restricted bird populations, especially birds that nest low on or on the ground,” the spokesperson said.

“It can also be a problem for birds that have evolved on islands where terrestrial predators would not naturally occur. It is therefore a good idea to limit new residential developments being built too close to important sites for ground-nesting birds, and to reduce or remove feral cat populations on islands where they do not belong.

Mike Toms of the British Trust for Ornithology (BTO), who was not involved in the study, said it provided “a welcome and much-needed global assessment of the impact that free-ranging cats have on wildlife”.

He said that [the study] highlighting areas of particular concern – such as the impact of cats on island populations – will help direct conservation actions to where they are most needed.”