“Silent Spring?” Ask the Cats

by Kevin Strauss

As the snow melts and the insects wake from their winter sleep, songbirds begin migrating from the south. Many insect-eating birds seem to follow the insect hatches north. After all, there is no sense moving north until there is something to eat here. Evolutionary scientists theorize that this behavior could be instinctive. Those birds who had the instinct (something we would term “common sense”) found food and survived. Other birds starved and didn’t pass their genes on to the next generation. But as the migratory songbirds move north this year, expect to see fewer than last year. Worldwide many songbirds species are in decline. About 25 percent of North American songbirds are declining, some with alarming speed. While in the 1960’s birdwatchers blamed declines on pesticides, today a major reason for the population drop in Minnesota could be much closer to home: housecats.

A recent study in Wisconsin estimated that feral and domestic housecats eat over 38 million songbirds (and 140,000 game birds) each year in that state alone. If other states saw similar levels of bird hunting, cats could be consuming almost two billion songbirds each year in the United States.

A proposal by one Wisconsin birdwatcher and hunter to allow the hunting of feral (wild) housecats as small game resulted in death threats against the man. While hunting might not be the most efficient way to get rid of troublesome feral cats, it is clear that these fast-reproducing predators are having a big impact on our bird population. Like any other non-native (some call them “weed”) species, domestic and feral cats have few predators in town. When turned loose they will hunt what their instincts tell them to hunt. Over millions of years, cats have evolved to hunt birds and rodents. They will keep doing that, even if well-fed by their owners. Hunting is an instinct for cats, not a choice. Asking a cat to stop hunting is like asking a human to stop breathing.

Some well-meaning cat owners have put bells on their cats to warn local birds. But cats are proficient stalkers. Bell-wearing cats can still catch birds. According to wildlife experts, the only way to keep a cat from killing birds is to keep the cat inside. Any outdoor cat is a bird-killer, pure and simple.

That is why feral cats can be so dangerous to the bird population. They are outside, and hunting, all the time. In the northwoods, foxes and coyotes can put a dent in the wild housecat population. But in other areas, cats, like pigeons and urban Canada geese have few natural predators and can quickly overpopulate an area.
Many of our most attractive ground-nesting and shrub-nesting songbirds are most at risk from hunting cats. Alien bird species like house sparrows and grackles have long lived near humans and have adapted to avoiding cats. Many native species have not.

While the Wisconsin legislature has to wrestle with whether or not to allow hunters to shoot wild cats, we all need to realize one inescapable biological fact: more cats means fewer birds.

Are we really ready to give up our spring birdsongs, and the income we are seeing from birdwatching tourism, to feed herds of feral housecats? Are we content to have house sparrows and grackles as the only birds we see at our houses? Given the impact of cats on birds (not to mention sandboxes), should we continue allowing free-roaming cats in our communities?

These won’t be easy decisions. Tempers will probably flare. And we may decide that cats are more important than birds. But we should be aware of the choices we are making and how that could give us a future silent spring.

The Ely Timberjay