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Beneath its adorable exterior, is your cat hiding the heart of a killer? Researchers now estimate that each year, domestic cats kill billions of birds and mammals in the United States alone. The report is in Nature Communications. [Scott R. Loss, Tom Will and Peter P. Marra, The impact of free-ranging domestic cats on wildlife of the United States]
We already knew that domestic cats can wreak havoc on islands, causing 14 percent of species extinctions and ranking as one of the world's 100 worst invasive species. But now, scientists have reviewed previous studies to find just how much damage cats do on the mainland.
Cats kill some 1.4 to 3.7 billion birds and 6.9 to 20.7 billion small mammals in the U.S. each year. These numbers mean that felines may be the biggest human-related cause of death for American birds and mammals. And cats tend to prey on native species, which can cause major ecosystem damage.
The worst feline killers are those without owners, and reducing feral cat populations is an ongoing problem. But you can still reduce the impact of domestic cats by keeping your pet indoors, thus leaving the neighborhood a little less red in tooth and claw.
—Sophie Bushwick
[The above text is a transcript of this podcast.]
Also see: Hannah Waters, Cat Are Ruthless Killers. Should They Be Killed?
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12 Comments
Add CommentUm, I don't think you understand one little aspect of cats: THEY'RE PREDATORS!!
Reply | Report Abuse | Link to thisYou would turn on our allies in the war on vermin so quickly? Do you not remember what happened the last time cats were slaughtered and rat populations went unchecked?
Reply | Report Abuse | Link to thisKeep your cats indoors and don't feed the feral ones. Let nature restore balance ...
Reply | Report Abuse | Link to thisPeople allow too much emotional involvement when it comes to cats. Emotion needs to be separated from facts. "Domesticated" cats, as we know them, are not native to North America. The feral cats are like any other feral species and are invasive that do not belong in the environment where they do not maintain a normal balance in nature. The problem is people love cats. I fail to see people coming to the rescue of things like Feral hogs or feral Burmese pythons in the everglades. No one has [problems with killing the invasive Norwegian Rat either.
Reply | Report Abuse | Link to thisWhen to comes to feral cats, we have to have an approach of science and facts and separate our emotions from them. Cat owners also need to be responsible with spaying and neutering. Exactly as I did with my cat that just passed last year at age 23 and lived indoors.
The simple fact is invasives are not good for the natural balance of species in the environment, even when they are cute or pretty.
This article seems to conflate pet cats and feral cats under the term "free-ranging cats", although it does seem to say feral cats are the bigger problem. I suspect feral cats are 99% of the problem, and think that's what we should concentrate on, leaving spayed/neutered Mittens and Fluffy to wander the neighborhood in peace.
Reply | Report Abuse | Link to thisInteresting article, but has anyone studied the impact on the "small mammal population" of human intervention? I'm guessing that grain production and ready access to food supplies in many homes might have led to an increase in those populations. We might be giving with one hand what we take away with our cats.
Reply | Report Abuse | Link to thisIt never ceases to amaze me that those who most vocally thrust evolution by natural selection with the emphasis on competition upon us go all queasy when they actually see it happening. One of the most obvious evolutionary advantages of the latest epoch has been the ability to tie your fortunes to those of the human race and make yourself indispensable whether this be by meeting practical or emotional needs. Cats have done both, in spades. They won. It's a little late, and frankly utterly pointless, to bleat about it now.
Reply | Report Abuse | Link to thisI kept cats for many many years until I realized how much damage they do to my beloved birds and squirrels.
Reply | Report Abuse | Link to thisThere is no "balance" to Nature. It's always in flux.
Reply | Report Abuse | Link to thisWhy do so very many people pretend there is some ideal distribution of life forms on Earth, usually dating to before the industrial revolution (or perhaps the spread of agriculture)? All species are invasive at opportunity. Yes, many piggybacked on human travels (voluntarily or otherwise) nut many do so all by themselves. That's why there are so many species "threatened" on islands that did not originate there.
Reply | Report Abuse | Link to thisEver since humans began to preserve and store food stuffs, we have had a problem with vermin, most notably rats. The domestic cat is in fact the result of food storage and later agriculture. Breeds like the Siamese, who are prized for their ability to control snake populations, in places where venomous snakes are a problem, are not particularly good for rodent control. They tend to hunt in trees more than other cats and so should be avoided in areas where venomous snakes lurking in your shade trees is not a concern.
Reply | Report Abuse | Link to thisThe best cats are American shorthairs, they very rarely bother with anything in a tree and will keep even an inner city rat population at bay. It really gives one an appreciation of what our symbiots have done for us throughout our shared evolution, to see Tigger going toe to toe with a rat that out weighs her, in your childs play room. Let's be honest, the "factory rats" that live on our coastlines and along our rivers are not native and the numbers of rats and mice that live in association with humans are not "natural" either.
Of course, almost all cats should be spayed or neutered, as they are prolific breeders and can live well into their 20's. But there is nothing like a fully vaccinated, parasite free Kitty cat, to protect your family from: rabies, lyme disease, infectious dysenterie, bubonic plague, still a danger in the American west, and other rodent vectored diseases.
I wonder how many of the 20.7 billion small mammals devoured by cats each years are of the disease-carrying rodent variety. Don't think cute little cartoon mice. Think vile, plague-carrying rats spreading Black Death across Europe and killing millions of people. Mice, rats and other rodents are direct transmitters of Hantavirus, Salmonellosis, Tularemia and Plague, among other potentially lethal diseases, as well as being indirect transmitters (by carrying fleas, ticks, lice and mites) of several varieties of Tick Fever, Lyme Disease, 3 kinds of Typhus.....well, you get the idea.
Reply | Report Abuse | Link to thisPerhaps instead of villainizing them, we should be grateful to our feline friends for doing their part to decimate the potentially disease-ridden and dangerous rodent population.