Birds & Birding

Is Your Kitty Cat a Destructive Killer?

February 22, 2013

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Cats kill billions of birds each year. Credit: Flickr/dr_relling

Does the loss of bird populations begin with a meow?

When most conservationists think about the biggest human-caused threats to native birds, they list things like oil spills, habitat destruction, invasive species, climate change, collisions with windows, pesticides and wind turbines.

But those threats, serious as they are, pale in comparison to what may be the number one killer of wild birds: Cats.

That’s right. Your beloved Tabby could be a wildlife destroying machine, a genuine conservation threat.

That’s what researchers suggest in a recent paper published in the journal Nature Communications. They found that free-ranging cats killed between 1.4–3.7 billion birds and 6.9–20.7 billion mammals annually in the United States.

That research has been widely publicized by birders, and widely ignored by everyone else. Especially cat lovers.

Researchers Scott R. Loss and Peter Marra of the Smithsonian’s Migratory Bird Center and Tom Will of the U.S. Fish and Wildlife Service Division of Migratory Birds suggest that feral cats (those not owned by someone) kill the majority of birds.

But still, a simple way to save the local fauna is to keep your Siamese or Manx indoors, or on a leash.

Bird Versus Cat. Bird Lover Versus Cat Lover.

The researchers hope their findings lead to solutions for free-roaming cat management. But maybe they shouldn’t be too optimistic.

Conservationists and outdoor enthusiasts have a special fondness for birds. We put up backyard feeders. We list them, we count them for citizen science projects, we marvel at their migrations.

The problem is, it would appear most people love cats even more. (And the native voles, shrews and chipmunks that cats gobble by the billions? They lack a fan base, even though they’re vital parts of the ecosystem).

According to the study, the United States is home to 84 million owned cats and another 30 – 80 million unowned cats (which includes truly feral felines and those living in fed but free-roaming colonies).

As environmental writer Ted Williams claimed  in Audubon, “The political power of wildlife advocates is dwarfed by that of the  feral cat lobby.  Last year, for example, it squashed federal legislation to remove exotic species from national wildlife refuges because feral cats might be among them.”

Kitty Nation

People love their pets, of course, and it’s quite possible to own a cat and not decimate the local songbird population.

More problematic is that many people now feel similar affection for feral cats.

There are many clubs and advocacy groups — with clever names like Alley Cat Allies — devoted to feeding colonies of feral cats, which essentially bolsters the population. Like other predators, cats will hunt and kill even if they’re not hungry—it’s their biological imperative.

To be fair, some of these stray cat activists promote programs where feral cats are trapped, neutered and returned. In theory, this would reduce the cat population over time.

In practice, there is no evidence this works. On the contrary, colonies of cats encourage people to release their unwanted pets at the feeding sites, and the overall population continues to climb.

Other cat lovers claim that cats have just replaced other predators that can’t coexist with humans in their suburbs and cities. I understand that point of view. But free-roaming cats are subsidized with food and shelter from humans, so they exist at much higher densities than other predators.

Save the Birds, Control Your Pet

As with most conservation issues, this one is about values as much as science. Some people see cats, including free-roaming ones, as an important part of their local fauna.

Others observe them stalking birds at their bird feeder and have a visceral negative reaction—as I did, when a cat interrupted my recent participation in the Great Backyard Bird Count.

I understand the devotion people feel for their pets, and for cats in general. But I come down on the side of the birds (and the voles and shrews). It’s time to start having hard discussions about managing feral cats.

In the meantime, you can make an immediate difference for bird conservation. It does not involve politically difficult and expensive solutions, like addressing energy development or sprawl.

You simply have to control your cat. It’s a scientifically valid conservation action that you can take today—and know that you’re saving countless songbirds and small mammals.

Photo Credit: Flickr/dr_relling under a Creative Commons Attribution-Share Alike 2.0 Generic  license. 

Join the Discussion

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  1. Licensing and laws do nothing to curb the problem. If cats are required to be licensed then cat-lovers just stop putting collars on their cats, as they did by me. And they won’t even bother getting them micro-chipped, especially not that They want absolutely nothing that can hold them legally responsible, liable, and accountable for the actions of their cats. It’s why many of them even keep cats in the first place. We’re not talking about the topmost responsible citizens of the world, you know. They don’t want that responsibility of what their cat has done coming back on them. If they had even one iota of a sense of responsibility and respect for all other lives on this planet we wouldn’t even be having these discussions.

    On the other hand, I found something that DOES work, and works well, and works fast (well, relative to the years it takes trying to reason with deceitful and lying cat-lovers that accomplishes ABSOLUTELY NOTHING). Where I live cat-lovers have learned that _ALL_ cats, stray and feral, collared or not, ear-tipped or not (because TNR con-artist liars now just clip cats’ ears only, WITHOUT sterilizing or vaccinating them, to protect their hoarded cats from being trapped and euthanized), _ALL_ their cats are humanely shot on sight and buried whenever found away from supervised confinement.

    The ONLY thing that works is destroying any of their cats found outdoors off their property. They either learn to stop getting more cats that die under the wheels of cars or from animal attacks, or they finally learn how to be a responsible pet owner, respectful neighbor, and learn to keep their invasive species animal under confined supervision, as it should be. Win win win all around. You can either destroy their cat for them humanely, or let their lack of concern for their cat cause it to die inhumanely. By destroying their cat for them humanely you are showing them that you care more about their cat than even they do. A bullet is by far the most humane death that any free-roaming cat will ever meet. Anything else is all inhumanely downhill from there. Their only other options are being hit by cars, environmental poisons, cat & animal attacks, disease and parasites, freezing, etc., etc.

    You can’t train a cat to stay home but I found that, in time, you CAN train a cat-owner into being a responsible pet-owner and a respectable neighbor. Most of them are so phenomenally stupid, disrespectful, and criminally irresponsible though that you have to make at least 12-15 of their cats permanently disappear before they even start to figure out what they’ve been doing wrong all during their sorry, useless, and pathetic lives. (Though the ones by me were uniquely cretinized and lobotomized. I had to shoot and bury many hundreds of their cats before they started to learn.)

    If you live in an area where its not legal to use firearms to destroy any animal that is threatening the health and safety of you, your family, your animals, or property (as it *IS* legal in most every area of the nation — shoot to maim is animal cruelty but shoot to kill is a perfectly legal way to humanely destroy any nuisance animal on your own property); then check into laws regarding air-rifles with ballistics speeds of 700-1200 fps and using pointed vermin-pellets in no-firearms zones. Many of the newer ones even come with their own sound-suppressor designs built-in, being specifically designed for shooting vermin cats in urban areas, the demand is that great. Failing that, then there’s always the SSS and TDSS Cat Management Programs that are exploding in popularity worldwide. Shoot, Shovel, & Shut-Up; or Trap, Drown, Shovel, & Shut-Up. Both methods are legal on every square foot of this earth. No local laws were violated if it never happened.

    (Where cats have already learned to evade all trapping methods, then inexpensive generic 1-adult-strength acetaminophen (overseas a.k.a. paracetamol) pain-relievers are a more species specific vermin poison, available everywhere for pennies. MUCH safer for the environment and all other animals than the antifreeze and rat-poisons that cat-lickers have forced everyone into using. But you really do need to retrieve and dispose of that carcass safely so that native wildlife won’t die from the many diseases cats spread even after their death. I fed a shot-dead cat to some starving opossum once, starving from cats having destroyed all their foods. (2 adults and 3 offspring they had while under my care.) Those opossum then died from some disease in that cat. Leaving ANY cat, alive OR dead, out in nature is no better than intentionally poisoning your native wildlife to death. Cats truly are complete wastes of flesh, they can’t even be used to feed wild animals safely.)

    I don’t see anyone dumping cats where I live anymore. They don’t even adopt more than can be kept under lock & key 24/7. When driving through the area I don’t see even one cat on anyone’s doorsteps anymore. I always keep an eye out to see if there are more free-roaming cats that will have to be shot one day. And if I’ll have to leave fish-oil trails on all the roadsides again, leading right to my IR surveillance system and laser-sighted rifle. (Got more than 70% of the hundreds of them in the area this way. VERY effective if you have criminally irresponsible and criminally negligent cat-licking problem neighbors where you live too.)

    Leaving ANY of their invasive species cats outside in my area means certain death for that cat, their further existence can be counted in hours. You’d think everyone else could learn from this simple lesson. The quickest way to solve an unwanted animal and irresponsible pet-owner problem is to let everyone know that you will quickly and humanely destroy every last one of their unwanted, uncared-for, or unsupervised animals for them. They either grow up fast or, far more plausible, dump their animals elsewhere to become someone else’s problem.

    You just can’t be an enabler of criminally irresponsible spineless and heartless idiots — or they remain that way. (At least where you live, anyway.)

  2. Wow – those are some blanket generalizations. I’ve owned cats and none of your comments apply to me: “If cats are required to be licensed then cat-lovers just stop putting collars on their cats, as they did by me. And they won’t even bother getting them micro-chipped, especially not that They want absolutely nothing that can hold them legally responsible, liable, and accountable for the actions of their cats. It’s why many of them even keep cats in the first place. We’re not talking about the topmost responsible citizens of the world, you know. They don’t want that responsibility of what their cat has done coming back on them. If they had even one iota of a sense of responsibility and respect for all other lives on this planet we wouldn’t even be having these discussions.” I’m sorry you’ve had the misfortune of living next to irresponsible people, but not everyone who owns a cat fits that bill.

  3. I’m exhausted just reading that.
    I guess it is pretty much in the eye of the beholder. Where I come from , possums are considered to be disease-carrying vermin (bovine TB for starters) and are poisoned and shot assiduously. We do recognise the enormous damage that cats can do, but we also add rabbits,stoats and weasels to the list of totally undesirable species. None of these are native to our country and there-in lies the problem. Rabbits were introduced to provide food for humans. Weasels and stoats were introduced to keep them under control. Recipe for disaster. Many of our native birds nest on the ground and some are unable to fly so are especially vulnerable
    While I appreciate the enormous damage that cats do, I would hate to think that the answer is to be found in wholesale slaughter.

    1. You should be as exhausted as I was after ridding my lands of hundreds of vermin cats.

      You’ll have no other choice than “wholesale slaughter”. Even more-so now that I let Australia’s government know why native predators can’t even keep these invasive cat populations in check. When they too found that increasing Dingo populations did nothing to stop cats. (Read this original discovery of mine that I made a decade ago (following link), if you too want to know why. Even Australians didn’t know until I told them why their more recent Dingo experiments failed. They should have contacted me first, I could have saved them millions of their native-animals’ lives. )

      As for all the other proposed solutions, then this is a must-read for people who think that trapping or sterilizing cats is in any way a viable solution. (Prepared-text alert.)

      Here’s how these ignorant, self-serving, and uneducated TNR-advocates are destroying all life on the planet.

      The TNR CON-GAME

      FACT: Trap & Kill failed because cats cannot be trapped faster than they exponentially breed out of control.

      FACT: Trap, Neuter, & Release (TNR) is an even bigger abject failure because these man-made ecological disasters cannot be trapped faster than they exponentially breed out of control, and they also continue the cruelly annihilate all native wildlife (from the smallest of prey up to the top predators that are starved to death), and the cats continue to spread many deadly diseases that they carry today — FOR WHICH THERE ARE NO VACCINES AGAINST THEM. Many of which are even listed as bioterrorism agents. (Such as Tularemia and The Plague — Yes, people have already died from cat-transmitted plague in the USA. No fleas nor rats even required. The cats themselves carry and transmit the plague all on their own.)

      FACT: THERE IS ABSOLUTELY _NOTHING_ HUMANE ABOUT TNR. Nearly every last TNR’ed cat dies an inhumane death by road-kill, from cat and animal attacks, environmental poisons, starvation, dehydration, freezing to death, infections, parasites, etc. And if very very lucky humanely shot to death or re-trapped and drowned (the two most common methods employed on all farms and ranches to protect their gestating livestock’s offspring and valuable native wildlife dying from cats’ Toxoplasmosis parasites). This doesn’t begin to count the thousands of defenseless native animals that cats skin alive and disembowel alive for their daily and hourly play-toys. The only difference in destroying cats immediately and humanely instead of trapping, sterilizing, then releasing them to an inhumane death; is that money isn’t going into an HSUS or SPCA board-member’s pocket, veterinarian’s pocket, cat-food company CEO’s pocket, or a drug-company CEO’s pocket. And that’s the ONLY difference!

      FACT: Cats are a man-made (through selective breeding) invasive species. And as such, are no less of a man-made environmental disaster than any other caused by man. Cats are even worse than an oil-spill of continent-sized proportions. They not only kill off rare and endangered marine-mammals along all coastlines from run-off carrying cats’ Toxoplasma gondii parasites, they destroy the complete food-chain in every ecosystem where cats are found. From smallest of prey gutted and skinned alive for cats’ tortured play-toys, up to the top predators that are starved to death from cats destroying their ONLY food sources. (Precisely what cats caused on my own land not long ago.)

      FACT: Hunted To Extinction (or in this case, extirpation of all outdoor cats) is the ONLY method that is faster than a species like cats can exponentially out-breed and out-adapt to. Especially a man-made invasive species like these cats that can breed 2-4X’s faster than any naturally occurring cat-species.

      FACT: In _TWELVE_YEARS_ Alley Cat ALL-LIES of NYC have only reduced feral cats in their own city by 0.08% to 0.024% (as the months go on that percentage becomes more insignificant), allowing more than 99.92% to 99.976% to exponentially breed out of control. Here’s how Alley-Cat-ALL-LIES’ deceptive math works: If you TNR 4 cats and 3 get flattened by cars this translates to 75% fewer feral-cats everywhere. Alley Cat ALL-LIES can’t even reduce cats in their own city, yet they promote it as a worldwide solution. Then even bigger fools fall for it and promote it.

      FACT: When researching over 100 of the most “successful” TNR programs worldwide, JUST ONE trapped more than 0.4%. Oregon’s 50,000 TNR’ed cats (the highest rate I found) is 4.9% of all ferals in their state. Yet, by applying population growth calculus on the unsterilized 95.1% they will have trapped only 0.35% of all cats in their state sometime this year. Less than 0.4% is a far cry from the required 80%-90% to be the least bit effective.

      FACT: Their mythical “vacuum effect” is a 100% LIE. A study done by the Texas A&M University proved that any perceived “vacuum” is just the simple case that CATS ATTRACT CATS. Get rid of them all and there’s no cats there to attract more. I proved this myself by shooting and burying hundreds of them on my own land. ZERO cats replaced them FOR 3 YEARS NOW. If you want more cats, keep even one of them around, more will find you. That university study also found that sterilized cats very poorly defend any territory. Non-sterilized cats, being more aggressive, take over the sterilized cats’ resources (shelter & food if any). If there is any kind of “vacuum effect” at all, it is that sterilizing cats cause non-sterilized cats to restore the reproductive void.

      FACT: During all this investigation I have discovered something that is unfaltering without fail. Something that you can bet your very life on and win every last time. That being — IF A TNR CAT-HOARDER IS TALKING THEN THEY ARE LYING. 100% guaranteed!

  4. Sorry my english,wenn cats are onli in rooms ,this is not good!cats want smell ,look.. Better you buy no cats,and the american way with “chain”(i dont now another english word)i hope you understand..PLEASE DONT BUY CATS where they life its onli a “cage”

  5. If TNC wants to get more donations, they should remove this erroneous, disturbing and controversial blog. I was looking for a land-protecting charity to support and, like many animal-lovers others I know, will be forced to choose another. When you look at the (very clear) big picture, you will see that HUMANS are the far larger and destructive threat than some innocent felines who ALSO pick up the slack where Bobcats and other felines have been extinguished (yet again, thanks to HUMANS). ANYONE can do a quick search under “NASA” and “Urban Sprawl” and learn of the reckless worldwide destruction of global forests, wetlands, etc. For what? For HUMANS – who *should* be implementing REGULATORY SMART GROWTH REGULATIONS – GLOBALLY. For the record, it is widely the HUMANS who bring the cats and irresponsibly maintain them. I’ve seen cats ALSO preying on mosquitos that can carry West Nile, etc and MICE who WILL live in your house (whether or not you realize it – unless you mouse-proof your home as best as possible) and the rodents WILL bring disease carrying TICKS with them. HUMANS die from Lyme’s disease too – while outdoor cats will NOT bring them inside unless you let them.
    WAKE UP.