Suppose that about half the households in your area had wild African lions or grizzly bears that they released out the back door to roam the neighborhood every evening.
That would add an element of excitement when it came time to take out the garbage, wouldn't it?
On a different scale and to the peril of a different set of potential victims, something quite similar happens every day and every night.
Songbirds and other small wildlife are at risk above and beyond what they naturally face because of subsidized predators â “ domestic house cats. These felines, pets mostly, are tame versions of wild killers, and they're taking a big chunk out of vulnerable wild species.
Recently, another study confirmed the predatory truth about house cats. This time, a Canadian governmental study essentially rubber-stamped the findings of previous studies conducted in the United States and Great Britain: cats are killing huge numbers of native birds and other small wildlife.
The Canadian study calculated that, of 25 considered sources of mortality to birds, predation by domestic cats is clear and away the No. 1 killer. By studying sample cats and figuring on the number of house cats across that country, it was estimated that domestic kitties kill maybe 200 million birds annually in Canada.
It's a familiar finding. Similar study in the U.S. has deduced that untold millions of birds, hundreds of millions, are cat-killed every year across America. When you get into small mammals, everything from mice up to rabbits and squirrels, it has been speculated that perhaps a billion (that's with a "b") of them die at the paws and jaws of house cats each year.
Some of the findings of these studies are ...
n Owned pet cats are killers instinctively, and it makes no difference if they are well fed at home. Some prey they kill is eaten; some isn't. But food isn't the driving factor.
In one experiment, six different cats were provided their preferred food, and while each was eating, it was also presented with a small, live rat. In all six cases, the dining cat stopped eating, caught and killed the rat, then left it to go finish eating its preferred food.
n Cats that wear a collar fitted with a bell are able to prey on birds and small mammals just the same. Apparently birds and prey animals don't naturally associate the sound of a bell with danger. In many cases, a cat learns to wait in an ambush position, only moving at the last instant to spring onto prey, making a bell a too-late means of alert.
Researchers said some belled cats may learn how to maneuver without bells sounding any alert to potential prey.
n Cats that are declawed aren't necessarily removed from the ranks of predators. A researcher said one declawed cat involved in study was one of the most prolific songbird killers of all observed. Declawing may put them at a disadvantage on defense, but it obviously doesn't stop their ability to catch and kill.
n Most predation by cats goes on without the cats' owners being aware of it. Some cats bring home trophies of their hunts, but many do not. Often the evidence of what's being killed is eaten â “ again, even by cats that are otherwise well fed.
Statistics don't bode well for birds, baby rabbits and such. About 77 million pet cats call the U.S. home. Almost two-thirds, some 65 percent of these, are either outside cats or are allowed to roam outside part of the time. (Conversely, only 35 percent are exclusively indoors cats.)
Along with these, scads of feral, homeless and free-ranging cats are on the scene. Various estimates put those at 60 to 100 million across the U.S.
Those free-ranging pets and feral cats are not a part of the natural eco-system. That is, nature didn't equip our wild community to cope with killer cats. The domestic cat, after all, is an exotic, stemming essentially from African wild cats first domesticated in Egypt thousands of years ago.
It's not only small prey creatures that suffer from cat predation. So do native predators. We generally applaud the elimination of such pests as mice. But think about that: Heavy cat predation on small mammals actually thins the food base for the native predators like foxes, hawks and owls â “ and all that stuff has to make a living on small prey.
I can measure it anecdotally but clearly in another way. When neighborhood cats are plentiful, I hardly see any rabbits in the yard. When it cycles down and the neighborhood cat population gets low, bunnies become routine again.
And that doesn't begin to address what effect cats have on songbirds or their vulnerable nests in shrubs and such.
Wildlife biologists and even pet advocates say the best that can be made of the situation is for pet cats to be kept indoors all the time. Inside cats live healthier, safer and longer lives â “ and keeping them inside lets wildlife get by without having to tolerate one more deadly, man-introduced factor.
Steve Vantreese, a freelance outdoors writer, can be contacted at firstname.lastname@example.org.