Cats have been called “highly effective killers”: they exterminate rare animals

Cats eat 2,000 species, including hundreds that are at risk. The first study to quantify what our felines eat on a global scale has found that the cute cats have a significant destructive impact on wildlife.

Cats may be beloved companions to humans, but they are also highly efficient killers, according to a study that shows they eat more than 2,000 species of animals around the world, including hundreds of species of conservation interest.

According to The Guardian, since domestication 9,000 years ago, domestic cats have spread to every continent except Antarctica. In a paper published in Nature Communications, researchers describe them as “one of the world’s most problematic invasive species.”

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

The cat menu includes birds, mammals, insects and reptiles, 17% of which are the first to quantify their diet on a global scale, according to the study.

In total, cats consume 981 species of birds, 463 reptiles and 431 mammals, accounting for about 90% of the species consumed. They were also found to feed on 119 species of insects and 57 amphibians, writes The Guardian.

Cats are especially dangerous on islands, where they eat three times as many species of conservation concern as they eat on continents. For example, they have been known to consume species that are now extinct in the wild, including the New Zealand Stephens Island rockwrens and New Zealand quail.

The impact of kitties on wildlife has sparked fierce debate in New Zealand, where one politician is campaigning for their complete eradication and controversy has erupted over competitions encouraging children to shoot feral cats.

In Australia alone, cats are estimated to kill more than 300 million animals each year, and conservation groups are calling for cats to be kept indoors. Some places have introduced quarantine measures for cats. In the southwestern German town of Waldorf, people have been ordered to keep their cats indoors for three months in the spring to protect the endangered population of crested larks that breed during this time.

Previous research has shown there is a “significant blind spot” when it comes to countering the “large-scale negative impacts” of domestic cats on local 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 eaters. “Cats basically eat what they have,” the researchers write. “If a species is missing from the diet analysis, it is likely that prey is either absent or rare in the environment.”

Scientists arrived at these figures by analyzing hundreds of existing studies. They believe their final estimates are conservative and will increase as more research is conducted. Their study looked at free-ranging domestic cats. Some of the larger animals included in the total may be eaten by cats, but are not necessarily caught as prey.

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

“Beyond gardens, cat predation can cause particular problems for vulnerable and limited bird populations, particularly birds that nest low to the ground,” a Royal Society spokesman said. “This could also be a problem for birds that have evolved on islands where land-based predators do not occur naturally.” Therefore, it is a good idea to limit the construction of new housing developments too close to important ground bird nesting sites and to reduce or remove feral cat populations on islands where they do not belong.”

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

He said: “The fact that the study highlights areas of particular concern, such as the impact of cats on island populations, will help direct conservation action where it is most needed.”