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Outdoor cats are prolific killers, study finds
Free-roaming house cats kill an estimated 4 billion wild animals across the U.S. every year, including birds, mammals, reptiles and amphibians.
Wed, Aug 08 2012 at 12:57 PM
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Photo: Niels Hartvig/Flickr
Cat owners often wonder about their pets' secret outdoor lives, but few are curious enough to actually follow them around the neighborhood. And thanks to a new study by the University of Georgia and National Geographic, that isn't necessary: Researchers attached video cameras to 60 house cats that are allowed outside, hoping to learn how free-roaming felines spend their free time.
The answer? About a third of pet cats kill time by killing wildlife.
That may not surprise cat owners who regularly find tiny corpses on their doorsteps, but the study suggests house cats kill even more prolifically than many people realize. The researchers found the cats that killed did so about 2.1 times every week they spent outside, but brought home fewer than 25 percent of their kills. That could mean U.S. cats kill more than the previous estimate of 1 billion native birds and other animals every year — possibly as many as 4 billion.
"The results were certainly surprising, if not startling," says UGA researcher and lead author Kerrie Anne Loyd. "In Athens-Clarke County, we found that about 30 percent of the sampled cats were successful in capturing and killing prey, and that those cats averaged about one kill for every 17 hours outdoors, or 2.1 kills per week. It was also surprising to learn that cats only brought 23 percent of their kills back to a residence."
Working with National Geographic's Remote Imaging Department, Loyd and her colleagues attached lightweight video cameras (known as Crittercams, or "KittyCams" in this case) to 60 outdoor house cats in Athens, Ga. The cats' owners volunteered for the study by answering ads in local newspapers, and downloaded footage from the cameras at the end of each recording day. The study extended through all four seasons, and Loyd says the cats averaged five to six hours outside daily.
The cats killed a wide range of wild animals, including lizards, voles, chipmunks, birds, frogs and snakes (see the graph below). The study didn't include feral cats, but previous research suggests ownerless felines are at least as deadly as their more coddled cousins. A 2010 study by the University of Nebraska, for example, found that feral cats have driven 33 bird species to extinction worldwide, and that they prey more on native than non-native wildlife. In fact, since domesticated cats aren't native to North America, this leads some wildlife advocates to consider cats an invasive species themselves, on par with kudzu or Asian carp.
"If we extrapolate the results of this study across the country and include feral cats, we find that cats are likely killing more than 4 billion animals per year, including at least 500 million birds," says George Fenwick, president of the American Bird Conservancy, in a press release about the study. "Cat predation is one of the reasons why one in three American bird species are in decline."
"I think it will be impossible to deny the ongoing slaughter of wildlife by outdoor cats given the videotape documentation and the scientific credibility that this study brings," adds Michael Hutchins, executive director and CEO of the Wildlife Society. "There is a huge environmental price that we are paying every single day that we turn our backs on our native wildlife in favor of protecting non-native predatory cats at all costs, while ignoring the inconvenient truth about the mortality they inflict."
See the KittyCams website for photos, videos and data from the study. To get tips on keeping cats indoors, check out Ohio State University's Indoor Pet Initiative or the American Bird Conservancy's Cats Indoors Program. And if you know a cat that just can't be fenced in, you could at least attach a bell to its collar, or even dress it up in a bird-protecting "cat bib." (Fair warning: The cat may then want to kill you instead).
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Today it was revealed that Scotts Miracle-Gro was fined $12.5M for selling birdseed that kills birds. They submitted false documents to the EPA and kept seling the seed even though they knew it would kill birds and were told to stop by the government. National Geographic's campaign to blame house cats for the extinction of birds is a fraud designed to steer everyone's attention away from chemical manufacturers, the real KILLERS. BOYCOTT Scotts Miracle Gro, BOYCOTT National Geographic.
Statistical nonsense. How the heck do 20 cats killing 4 birds morph into billions? Spare me the "extrapolation". This just panders to the cat haters. How many birds and other wildlife are killed by other predators? By loss of habitat? By poisoning the environment? Get real. Stop blaming cats for everything an citing statistical claptrap to support it.
My cat Charlie is a big baby. He sleeps all day on my bed then goes out at night. Here's when he caught a baby bunny on Easter ironically. http://davewirth.blogspot.com/2011/04/easter-bunny.html
He didn't kill it or even hurt it. He just laid down next to it, when it would run away he would pick it up and bring it back to the patio.
Yeah my cat caught a giant adult bunny a few days before easter. It was crazy! I kept saying that he killed the easter bunny since it was so big haha.
Thank you so much for that story. It's awesome. So cute!
I once had an outdoor cat who would regularly kill squirrels and rabbits. One of my cats even killed a snake one day!
I'm all for the bird conservation thing, but I live in the country. Let's get real. Cats eat mice. Snakes eat mice. Cats eat the snakes' food. Snakes go away. That's why I have (and love) outside cats. I have curious kids, and their lives are way more precious to me than the birds and mice that my cats kill.
How many cats kill insects and other pests that species of birds eat?
Mine are afraid to go outside.
Makes me want to get two more cats.
I already knew this. The cat, whether it be a Siberian tiger, an African lion or the lazy little bum sleeping on your sofa, is the most perfectly-designed land predator there is. No other creature scores a kill more often than a cat. You simply couldn't design a better predator.
I hate cats!
People that hate cats are numb-skulls that have a brain cell missing.
jajaja
Your hating cats is unfortunately a loss for you. They are wonderful and affectionate companions. My grandson, who is very allergic to their dander, is constantly heartbroken that he cannot cuddle with my two loving felines.
I live in an area with mice, moles, volves and snakes! That is why I have a cat! What is the big deal?
Nah, I'll let my cat go outside as long as he wants. Thankfully he's taken care of any mice and that annoying gopher that tore holes into the ground.
Cats don't bread...they might eat bread though.
And open your eyes, the article DOESNT INCLUDE ferals.
And if he grabs a bird, oh well.
Really? Anti-cat propaganda. Probably written by someone who loves dogs. With the amount of foxes and coyotes running around ... cats fit in the food chain perfectly. These are not Asian Carp we are talking about. So stop whining and go eat nothing ... cause we know you don't eat meat and plants have feelings too!!!
I've noticed on forums that many dog lovers hate cats but I've yet to see a cat owner say they hate dogs.
I agree. Cats are clean, clever, cute, cuddly, soft and llove you once they get to know you. However dogs dribble on you, have their tongues hanging out all the time, roll around in their s***, eat their own s***. And you often hear about children being mauled by mutts. Never cats.
Two cat house here. I hate dogs BUT I would never cause one harm.
The owner maybe, cos they're stupid if they don't teach the dogs to SHUT UP and stop howling like a pack of coyotes (the mutts next door...omg....)....they bark late at night...they howl at day, theyre' annoying...
honestly, i dont mind dogs..it's the irresponsible, inconsiderate owners...silly dogs seem to gravitate to me cos they know a sucker when they see one haha
Dog lovers typically love being the master in the relationship getting unconditional love and affection from their dog, while the non-compliant cats is to be too much for their egos to handle.
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