Wednesday, January 30, 2013

Feral Cat Lovers Learn Science Isn't for Sissies

Over at the Scientific American Culturing Science blog, they boldy look at the numbers:

Every few months, the fact that domestic cats are ruthless killers hits the news. This past summer it was the Kitty Cam, memorably explained by webcomic The Oatmeal, which saw nearly one-third of cats kill 2 animals each week on average. In 2011 a study found that domestic cats were responsible for nearly half of predation on baby gray catbirds (Dumetella carolinensis), a shy bird common in the mid-Atlantic and named for its cat-like call. And this morning, Nature Communications published a large analysis estimating how many animals are killed by cats annually in the US: 1.4-3.7 billion birds and 6.9-20.7 billion mammals each year.

Let me repeat: every year BILLIONS of birds and mammals are killed by free-ranging domestic house cats, Felis catus. And millions of reptiles and amphibians on top of that.

This is not a cue for you to pat Fluffy on the head and congratulate her for being such a “natural little killer.” These data are no joke. Domestic cats are on the IUCN’s list of the top 100 World’s Worst Invasive Alien Species for their ability to decimate prey populations. Those razor-sharp claws strike the hardest on islands, where animal populations are relatively confined. A 2011 review found that, on islands, cats are the primary cause for at least 14% of bird, mammal, and reptile extinctions and the principal threat to almost 8% of critically endangered animals (2).

The new data drive home the point that, even on large continents, cats can do serious damage. Easily more damage than collisions with buildings or wind turbines do to birds. And, the authors hope, it’s a fact that wildlife management groups will not be able to ignore.

Feral cat populations are out of control–but what can be done about it?

Now we come to the bold part:

The problem is that trap-neuter-release programs don’t work. Cat fertility is so high–a single female can have 3 litters of 4-6 kittens each year–that a just a small percentage of the population needs to be reproductive to make up for the natural death rate. (Even if most of the kittens born end up dying before reproducing.) Additionally, trap-neuter-release isn’t even cost-effective compared to euthanasia, even if all the cat feeding, capturing and neutering is performed by volunteers.

And, meanwhile, all those neutered cats are still doing what they do best: catching and eating small animals.

So the obvious answer then is that, if we value biodiversity and wildlife and can manage to overcome our predilection for cute cat faces over cute bird faces, cat populations should be controlled through humane killing, just like many other invasive species.

Right.  But....

But the funny thing is that no one suggests that. In compulsively researching this blog post, I read many papers showing that trap-neuter-release doesn’t work, or studies showing that, in computer models, euthanasia reduces cat populations more effectively than trap-neuter-release. But then in their concluding paragraphs, after providing evidence that current methods aren’t working, the action steps proposed by the authors are: (1) all pets should be neutered and (2) owners should be be better educated so they don’t abandon their cats.


Look, I’m as sentimental as the next person. (I cried for the entirety of Les Miserables.) I love my cat and she gives my life meaning. But I also can admit that the science is staring us in the face. We can’t bear to talk about euthanizing cats because they are so friggin’ cute–but, if we’re honest with ourselves, the best solution to this problem is to kill cats. Kill them, with their cute little faces, their soft fur and their snuggles. Some of the cats need to be dead.

Yep, this is Scientific American
 Read the whole thing.  I quote so much here only as an antidote to the fact that people are lazy.



geonni banner said...

"The Wildlife Society was one of few groups I found willing to advocate for feral cat euthanasia, after seeking out adoption. The other, surprisingly, was PETA–for the reason that feral cats live short, brutish lives."

What!?! PETA? Oh yeah... The group that wants ALL domestic animals eradicated. Well, DUH.

Marie said...

I find the vast majority of cat owners to be irresponsible. They allow their cats to roam and I doubt if they ever get them inoculated for rabies. I highly doubt most of them have ever even been to see a vet for general health care. I live in a semi-rural area, I don't see many dogs roaming around, but there sure are plenty of cats. I don't want them on my property period. They kill the birds and small mammals that we enjoy having here, they pee, poop and whatever by us. I am seriously thinking of getting a .22 as it's getting worse. And I don't want my terriers tangling with feral cats - I have never understood the T/S/R mentality, feral cats are not your house kitty, they are wild just like the other wild critters out there.

SecondThoughtsOptional said...

Marie, if cats were like their wild progenitor, there wouldn't be anywhere near as big a problem. The wildcat is solitary and each has a territory of at least 1 square kilometre under good conditions (under all conditions, male ones are bigger and overlap several female ones). We'd not see anything like the impact of dozens, if not hundreds of cats per square kilometre as we currently do.

TNR for feral cats is a curious blindspot. We don't do that for any other domestic animal I can think of.

There is no TNR for feral dogs -- we recognise their capacity for harm and disease spreading. There is no TNR for ferrets, which hunt similar-sized prey to cats -- feral ferrets are quickly declared pests and hunted down. There is no TNR for feral horses or cows -- where they are tolerated, their population sizes are monitored and kept in check by rounding up and removal or culling. There is no TNR for pigs or goats or sheep. There is no TNR for rabbits, rats, mice, escaped exotic birds, fish or reptiles. These animals are all much-loved, valued and valuable domestic animals -- yet their capacity for harm in the environment is acknowledged and kept in check.

It's strange that this anomaly exists among too many cat-lovers (I love cats, but mine were strictly indoor pets), that belief that the depredations of a hyper-abundant carnivore just aren't important. And it needs strong challenge.

Liz said...

It is with sincere love of cats (there's one currenly napping on my shoulder) that I say the socially responsible view of cat ownership needs to change. Free-roaming cats in my neighborhood chase away birds of all kinds, harass my chickens and mess up my garden. Indoor-only cats are perfectly happy, healthier and live longer. If the standard of cat ownership became indoor-only, it'd be quite easy to reduce the numbers of feral or semi-feral ones. Just shoot the ones outside.

If the owner of iguanas or boa constrictors let them "free roam" outside, they'd be quickly brought in as a public hazard.

lance said...

I can't find the reference at this moment but at least one mid-western university has published a paper discussing shooting as the most sensible feral cat control method in rural areas ( my friends tell me Airedales are a close second), think it was Iowa state. It's funny that we can have 10 reality shows in prime time about feral hog hunting and the cat ladies are first on scene to demand death for feral dogs and coyotes but somehow cats and horses are tooooo magical to kill, we must rehome them or store them in a safe place till they die of old age!!!!! The tide is turnIng though and I think more states are going to ban TNR. Almost all states now have laws against releasing invasive species anyway so most TNR programs are already in violation. In the only unbiased study TNR has resulted in INCREASED cat population since many cat diseases are spread by fighting which in cats is driven by sex hormones and toms regularly practice infanticide against kittens to cause queens to come into heat. The decrease in mortality and increased tolerance for population density ( decreased territorialism) more than outweigh any decreased fecundity.

Anonymous said...

I agree that feral cats and feral horses should not be treated differently from feral dogs or hogs, when the harm being done is comparable. People created this problem and people need to fix it! I've appreciated this discussion of the blind spots and failings of the TNR solution.

But the eradication of the indoor/outdoor house cat is a totally different issue than the eradication of feral colonies. I doubt that indoor-only cats experience the same quality of life, health, and happiness as cats that get to go outdoors. Do indoor-only dogs, or indoor-only humans? As for the ecological implications: no matter how detrimental the net effect of cat predation is, it doesn't follow that every cat who hunts is part of the problem. There are neighborhoods whose cats have not made an appreciable dent in the local populations of the native birds and animals they hunt.

So I would worry about outdoor pets only in the case of a locally threatened species; otherwise, focusing on feral colonies seems like the best start to addressing the problem.

lance said...

Dogs can be leased, fenced and fairly readily caught when they stray. None of those concepts readily (using common practice) apply to cats. However I will grant you that the number one isuue is the group feeding sites that have proliferated in the past 20 years. When I was a child in the oh so distant 80's people fed their cats which were mostly indoor/outdoor fixed cats. When strays showed up they were typically chased off or captured a sent to AC. Today I have 3 different loonies withins two blocks of my house who put out gallons of cat food at multiple sites to feed the darn ferals. This easy source of nutrition leads to greatly increased fecundity and kitten survival. So if we could stamp out group feeding then the problem would start to improve. My main argument is that in wild spaces (anything past the end of mowed lawns) cats should be managed as a an invasive wildlife issue and not mollycoddled as pets. That goes triple for horses since they are damaging the habitat itself and potentially irrevocably do in arid region.

Anonymous said...

Lance --

Too lazy to look up the study, but I've also heard that the tom cats who are going soft and letting their offspring live and stick around are then reproducing with them, so that it is taking very little time for some feral colonies to become disastrously inbred. It sounds like we've witnessed the same kind of loonies so you've probably also seen how ugly this can get.

I explained some reasons for distinguishing feral cats from the fixed indoor/outdoor cat (at least in the right neighborhood), but I thought about it some more after reading this post:

The feral cat hoarder apparently just wants to keep cats alive, no matter how sick or miserable. The indoor-only advocate additionally wants to keep cats fat and content. The typical TNR advocate, I think, would like all cats to be fat and content, but wants to avoid killing cats who can't find an indoor living situation. Maybe there are also TNR advocates who think cats are wild animals (noble savages?) that should roam free, killing whatever they want and reproducing at will.

Whichever position is best, all of these positions are also held by people about people. Maybe people are consistent about what they think is best for animals in general -- or maybe it's really hard not to project a bit?

Maintaining a steady level of respect for (or at least, interest in) what cats are about *as cats* seems like a really helpful check. And if we really like cats, it's something we want to do anyway! Especially when it comes to the individual cats in our lives, who often seem to have different priorities.

But it astonishes me that even purebred Persians chatter at squirrels from the window, practicing a spine-severing kill bite that their tiny jaws could probably not deliver. I suspect that the incredible interspecific social intelligence that makes cats so popular with humans is the same capacity used for psyching out prey or predicting prey's movements! So if we're uncomfortable with predation, we have a long way to go; the predatory instinct is not going anywhere soon.