It has always interested me that American robins are not particularly choosy when it comes to locations for constructing their mud and grass nests.
Over the years, I've observed pairs of robins build nests on a tractor and other machinery, on top of a fence post, on a windowsill, on top of an electric meter box and within the branches of a host of different trees and shrubs.
Knowing this behavior, I decided to place a simple little nesting platform onto a support pole directly underneath my house's roof overhang to see if a robin would use it. Sure enough, a pair of robins discovered it and built a nest on it. They're now busily feeding their hungry offspring.
Nearby, another pair of robins constructed their nest only two feet off the ground inside a clump of diamond willows. The nest's location makes it convenient for monitoring the chicks as I walked past it, yet I can't help but think how vulnerable they appeared to be. Indeed, any bird that nests on or close to the ground is especially susceptible to predation by predators.
After the robins had hatched and were more than a week old (there were three), I began to believe that maybe they wouldn't be discovered by a predator, and that maybe they would survive to fledge. However, as I drove out of my driveway a couple of days later on my to work one morning, I saw a house cat dart across the road from the vicinity of the willow-clump with - you guessed it - a robin chick clenched tightly between its teeth.
Many people own domestic cats - some 90 million pet cats live in the United States. Cats make wonderful pets, are generally easy to take care of and are usually very adept at catching mice. Yet, as efficient a predator a cat is, it is a cat's hunting proficiency that, paradoxically, adds a degree of imperfection to an otherwise extraordinary animal.
A house cat that hunts, captures and kills wild birds and animals is only doing what comes naturally. However, from my perspective, when a pet cat is allowed to roam the city streets or countryside fields, forests and roadside ditches to hunt out-of-doors, then it is not doing what's natural.
It is estimated that hundreds of millions of birds and small mammals are stalked and killed annually by domestic house cats. Without question, this excessive figure is testament to a cat's amazing hunting prowess, but it also illustrates an important inference: the number of deaths to wildlife would not be so high if domestic cats were prohibited from wandering outside in the first place.
Keeping house cats indoors is appropriate for many reasons that go well beyond the fact that wildlife die in their clutches. A cat that remains indoors, for instance, enjoys a much longer and healthier life. Untold dangers await all cats that are allowed the freedom to roam outside.
Vehicles, other animals, disease, parasites, weather and people are some of the many hazards an outdoor cat faces. Because of these threats - and more - an outdoor cat lives, on average, only two-five years, whereas, a well-cared for indoor cat can live as long as 17 or more years.
How many dead cats have you observed on the roadways? How many people do you know who shoot stray cats? How many sickly looking cats have you seen cross city streets? How many homeless cats have you had show up on your doorstep begging for food? And how many cats have you observed with mouthfuls of feathers or stalking birds at backyard birdfeeders?
To be clear, I have never supported allowing house cats to roam free. After all, Nature never intended for the domestic house cat to be a part of any natural and functioning ecosystem; the Canada lynx, bobcat, mountain lion, jaguar - yes - but not the domestic cat. Few predators are as efficient at capturing and killing their prey as cats - wild and domestic alike.
Here are some interesting research data for you to consider. Researchers at the University of Wisconsin completed a four-year study on rural free-roaming cats and, coupled with data from other studies, estimated that free-roaming cats in Wisconsin killed from 7.8 million-217 million wild birds per year.
What the researchers did not study were the effects to wildlife from suburban and urban cats. As such, it can be assumed that the actual number of wildlife deaths caused by free-roaming cats is much, much higher. And think about this: the study estimated that feral cat densities in some parts of the state reached 114 cats per square mile!
In a Kansas study of cat predation in an urban area, it was shown that 83 percent of 41 study-cats killed wild birds. Most of the cat owners were unaware that their cats were capturing and killing wild birds, until they found evidence of feathers in scat or observed the cat with a bird or found parts of the bird somewhere in the house. The study also revealed that one particular cat, a de-clawed cat, killed more birds than any of the other 40 study cats.
Another fact: As already mentioned, domestic cats do much better while spending their lives inside homes with their human caregivers. If a hapless mouse happens to get captured inside the house by the cat, then that's probably a good thing. But the perils of the outdoors are too many and our wildlife too important to allow pet house cats to run loose outside as we get out and enjoy the great outdoors.
Blane Klemek is the Bemidji area assistant wildlife manager, DNR Division of Fish & Wildlife. He can be reached at firstname.lastname@example.org