Tag: predators

No, A Study Did Not Conclude Cats Kill 20 Billion Birds And Small Animals Yearly

Talk to birders, casual conservationists or anyone who says they’re worried about the ecological impact of cats on native bird and mammal populations, and without fail they’ll bring up The Study.

Yeah, that one: A 2013 study, published in Nature Communications, that claimed cats kill “billions” of prey animals each year in the U.S. alone — including 3.7 billion birds and up to 20 billion small mammals in the contiguous states.

What activists won’t acknowledge is the fact that there are fatal flaws in the research, flaws that have been repeated in a new study claiming cats kill 10 times as many small animals as wild predators.

Let’s break it down:

The researchers don’t actually know how many animals cats are responsible for killing. Both the 2013 Nature Communications study and the 2020 Animal Conservation study rely on owner questionnaires to estimate the number of animals pet cats kill outdoors and to assign numerical scores to their cats’ “hunting skills.” In other words, the study authors are relying on people who have no idea what their cats are doing outside to give them supposedly accurate figures on how many birds, rabbits and reptiles little Fluffy and Socks kill every year. As for people evaluating the hunting skills of their cats, how exactly do they do that? Do they consult nonexistent scoreboards? Do they find a dead mouse or two and conclude that Socks is the GOAT hunter?

The people who took the surveys were self-selected. These aren’t random samples. The questionnaires were given to people who actively volunteered to participate in the studies.

catbird4
Friend or snack?

 

 

  • In both cases, researchers supplemented their questionnaire data with estimates of “additional” animals killed by cats. Or to put it bluntly, the research teams invented numbers and plugged them in. They’ll claim they arrived at those numbers via analysis, but again, these are studies that rely on owner questionnaires for the bulk of the predation data. Any conclusions drawn from that data are automatically suspect.
  • The 2013 study was centered around a meta-analysis of earlier studies, not fresh data. For the numbers they didn’t have, researchers derived figures from older published studies. For example, they added billions of “kills” to the tally and attributed those phantom kills to “unowned cats.” The problem? No one knows exactly how many stray and feral cats roam America’s streets and countrysides, a fact the research team admitted in the 2013 study: “no empirically driven estimate of un-owned cat abundance exists for the contiguous U.S.,” they wrote.
  • The best estimates claim between 20 million and 120 million feral and stray cats live in the contiguous U.S. That’s a spread of 100 million! How can a research team estimate how many prey animals are killed by cats when they can’t even get a fix on the cat population? The numbers matter: If there are only 20 million ferals and strays, each of them would have to kill more than 1,000 animals a year to account for the study estimates.
  • Headlines trumpeting the 2020 study say it’s based on GPS data, but that’s only partially true. Yes, the team used GPS data from a small number of cats belonging to self-selected study participants, but that data tells them nothing about how many animals those cats are killing. The GPS data only indicates where cats go when they wander, not what they do. In this study, as in the last, researchers relied on questionnaires, which in turn assumes cat owners have exceptional memories and can account for everything their furry friends do outdoors when no one’s watching them.

The stakes are high, as NPR noted in a story about the 2013 study: The resulting headlines are repeated as gospel in newspapers across the country and on countless news sites, which in turn influences how people feel about cats. They influence politicians and proposed laws as well, with several countries looking to ban outdoor cats.

Buddy's claws
One cat who has zero kills: “I am NOT an inept hunter! You don’t want to tangle with these talons, bro.”

Nuance, such as the 2013 study’s admission that an unknowable number of animals are killed by “collisions with man-made structures, vehicles [and] poisoning,” is usually left out of those stories.

After all, no one’s seriously proposing an end to the automobile industry despite studies claiming untold billions of animals die as roadkill annually.

A quick Google search turns up hundreds of articles with breathless headlines like To Save Birds, Should We Kill Off Cats?, The Moral Cost of Cats, and Cat Owners Turn Blind Eye To Pets’ Violence.  There are alarmist books, too, like the hysterically-named Cat Wars: The Consequences of a Cuddly Killer.

In some Australian territories, authorities have open bounties offering $10 for the scalps of adult cats and $5 for the scalps of kittens. Is this what we’ve come to? Killing baby animals based on hysteria over bunk science?

“It’s virtually impossible to determine how many cats live outside, or how many spend some portion of the day outside,” Wayne Pacelle, former president of the Humane Society of the United States, told NPR at the time. The scientists “have thrown out a provocative number for cat predation totals, and their piece has been published in a highly credible publication, but they admit the study has many deficiencies. We don’t quarrel with the conclusion that the impact is big, but the numbers are informed guesswork.”

And that’s the important thing here: Instead of calling for a mass culling of cats based on wild estimates of their environmental impact, we should be working cooperatively on solutions to curb their opportunities to hunt, starting with simple measures like keeping cats indoors.

We don’t need another study with wild estimates of feline impact on small wildlife. What we need are smart plans and the will to implement them as a society.

(First image credit Earth.com. Second image credit CatsAndBirds.ca. Third photo is Buddy, the Inept Hunter.)

 

Reason #138 To Keep Your Cats Indoors: Mountain Lions

Just to clear up any misunderstandings — and hopefully stave off more of those “Would a tiger and a house cat be good friends?” questions — cats aren’t down with each other just because they’re cats.

You won’t see a jaguar high-fiving a jaguarundi like “Sup bro? Hunt anything delicious lately?”

And you sure as hell won’t see your cat shooting the shit with a puma on your back porch, trading war stories about taking down prey.

Nope. To the puma, your cat is the prey.

That’s what happened early on Thursday morning in Boulder Creek, California, where footage from a Ring doorbell cam shows a puma — also known as a mountain lion or cougar — hovering over something partially obscured by a planter. There’s a flash of domestic kitty eyes for the briefest instant, then more noise followed by the puma walking away with the cat in its jaws.

Cougar/Puma
Despite their large size, cougars are not considered “big cats” and are not aggressive toward humans. Source: CBS2NY

Sue Ann Sheely, whose camera caught the attack, said it’s the second time she’s seen a local cat fall victim to a cougar. She sent the footage to a local news station so her neighbors will finally wise up and bring their cats indoors.

Like coyotes, pumas aren’t breeding in greater numbers or suddenly intruding on human territory: We’re the intruders, chipping away at the wild cat’s habitat with each new housing development and strip mall we build. The majestic-looking cats die in unusually high numbers when roads cut through their ranges, and simply brushing up against a human neighborhood is often enough to get them shot.

With fractured habitats and fewer prey animals to hunt, pumas will sometimes turn to domestic animals as prey. Attacks on humans are exceedingly rare, and pumas normally do their best to steer clear of humans.

Previously, we’ve looked at other reasons to keep your cat indoors: Reason #127 To Keep Your Cats Indoors: Bad Guys, Reason #246 To Keep Your Cats Indoors: Coyotes, and Reason #001 To Keep Your Cats Indoors: Traffic.

Jaguarundi
The jaguarundi may be small, but it doesn’t mess around. Credit: CostaRicaJourneys

Cats: Adorable Even When They’re Committing Murder

A few weeks ago I chanced upon the above image.

“What a cute kitty,” I thought, then squinted. “Wait… Is that a dead mouse clamped between her teeth?”

After zooming in and verifying that, yes, that is a poor rodent meeting its unfortunate end, I came to a profound realization: Cats are cute even when they’re committing murder.

Like this little guy below: Totally cute. Totally thinking about murder.

Cute cat and mouse
“My hobbies include eating, sleeping, knocking items off flat surfaces, and murder. I’m really passionate about murder.”

Think about that for a second. We love cats because they’re great companions. They’re loving despite all the myths that claim they’re not, they’re cute, and they’re endlessly amusing.

We welcome them into our homes, adjust our schedules to their needs, and fret about how they might not like a new brand of litter or a newly-arranged living room.

We laugh when they shred paper and enthusiastically tear into plush toys.

We trim their razor-sharp claws, kiss their little heads and give them names like Buddy, Gizmo and Puddin’ Head.

And yet cats aren’t just murderers, they’re serial killers. They’re the bane of birds, rodents and lizards on six of the seven continents. They’re so ruthlessly efficient at killing, in some countries it’s illegal just to let them outside.

Kitten With A Mouse
A serial killer in training.

Thankfully I haven’t had to deal with my cat bringing me “presents” of dead rodents or lizards. We live in an apartment, Buddy doesn’t want anything to do with the outside unless I’m with him, and if our games are any indication, he’s a hilariously inept hunter who probably couldn’t catch a rodent even if I slow-tossed one to him like a pitcher serving up meatballs in a home run derby.

Yet I’ve heard many stories from friends and acquaintances whose cats are little terrors. Murderous cats are even the subject of this week’s pet advice column on Slate, where a reader complains that her cat proudly presents her with dead mice, frogs and rabbits.

So what sort of powerful magic is at work here? Why do we disregard the murderous side of our little friends? Or is this the work of toxoplasma gondii, that infamous cat-carried parasite that is rumored to take over human brains?

In truth, it’s just who cats are. They’ve been companion animals for so long, it’s easy to forget the reason cats and humans came together in the first place was to kill rodents who were eating their way through stored grain in the very first human agricultural settlements.

So instead of fretting about their murderous ways, maybe we should just be thankful they’re not large enough to eat us too. Isn’t that right, Mr. Fluffy?

Cute Cat Killing Mouse
“What? Am I not cute even whilst committing murder?”
Buddy's claws
“I am NOT an inept hunter! You don’t want to tangle with these talons, bro.”