Cat predation on wildlife

Cats hunt small prey, and both feral and domesticated cats prey on wildlife. This is sometimes seen as a desirable phenomenon, such as in the case of barn cats and other cats kept for the purposes of pest control. In other cases, the effect of cats on wildlife is met with concern.

For thousands of years, cats have been known for their ability to hunt mice and rats and keep their populations under control. This ability is understood as the reason cats became domesticated. The relationship was more of convenience (or mutualistic) than dependence: "Cats killed mice and rats, and humans provided lots of mice and rats to kill since mice and rats lived in human settlements." A 2014 study examining 5,300 years of cat remains in an agricultural village of Quanhucun, China, provides early evidence of this dynamic, where cats protected grain stores by eating rodents.

If they are well-fed, farm cats are more dependable as effective ratters, as they are less likely to stray or hunt further afield. Cats are wary of adult rats, given their size, but are particularly adept at hunting young rats.

In 2002, feral cats introduced to a flower market in Los Angeles, California, were noted to have helped lower rat populations. In Chicago's 47th Ward, feral cats were introduced in 2012 to help the city deal with the rat problem there.

Efforts to eradicate feral cats in Ventura, California, were noted in 2002 to have resulted in increasing numbers of rats, which were being monitored for health problems such as bubonic plague.

A 2013 study by Scott R. Loss and others of the Smithsonian Conservation Biology Institute and the U.S. Fish and Wildlife Service suggested that free-ranging domestic cats (mostly unowned) are the top human-caused threat to wildlife in the United States, killing an estimated 1.3 to 4 billion birds and 6.3 to 22.3 billion mammals annually. These figures were much higher than previous estimates for the U.S. Unspecified species of birds native to the U.S. and mammals including mice, shrews, voles, squirrels and rabbits were considered most likely to be preyed upon by cats.

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Wikipedia