Conserving Thoughts: Owls — nature’s pest control

The more you learn about owls, the more you’ll be amazed and intrigued by these primarily nocturnal birds.


At the location of a well-known rodent remover were found the remains of 1,987 field mice, 656 house mice and 210 rats. As if those numbers weren’t impressive enough, consider that this pest controller provided its services free of charge and it was so un-intrusive most people in the area never even knew it was there.

And what is this mysterious, but masterful mouse exterminator? It’s none other than the bird we seldom see but are very familiar with — the owl. The data listed above is from a study conducted a number of years ago which involved dissecting owl pellets (the compacted remains of animals coughed up by owls) that were found at an owl site. The study didn’t mention the estimated time period over which the owl pellets were deposited or how many owls were using the site, but it doesn’t matter. When you consider those numbers represented the hunting results of the inhabitants of one owl site, one word comes to mind: Wow.

The more you learn about owls, the more you’ll be amazed and intrigued by these primarily nocturnal birds. You’ll also learn that some of the owl “facts” you’ve heard over the years aren’t true. For instance, an owl cannot turn its head in a complete 360-degree circle.

However, its range of head motion is greater than most vertebrates (approximately 270 degrees). This high degree of turning ability is a compensation for the fact that an owl’s eyes are fixed in their sockets. Unlike humans, owls can’t move their eyes from side to side and, as a result, they must turn their entire heads when they want to visually inspect something.

Another owl misconception is that the feather tufts sticking up from the heads of some species of owls are ears. They’re not, they’re feathers. An owl’s ear openings are within its facial disc. An owl’s facial disc focuses sound waves into its ears. The right ear opening is higher than the left, providing owls with sort of a “three-dimensional” hearing ability. This trait helps owls locate prey in total darkness by hearing alone.

Another owl fallacy is the concept of the “wise old owl,” a belief which probably originated with the ancient Greeks or Romans and was based on the owl’s nocturnal — and, thus, mysterious — routines and its haunting calls. Although owls look self-assured and stately, studies have shown that — compared to other wildlife species — owls don’t seem to possess a number of traits biologists equate with wildlife “intelligence.”

Nevertheless, they are highly efficient predators and can be beneficial to humans. Their predation skills have little to do with why people like hearing owls today, though. A big reason an owl’s call is such an attention-getter is that it’s rarely heard by most people. Not that owls are rare — on the contrary, several species are found in Missouri. It’s just that owls are out and about at a time of day when most humans are inside and in bed. However, if you want to try to hear one, now is a good time to start listening.

Owls are active throughout the year, but winter is when most owl species begin courtship and nesting. Consequently, from now until early spring is a good time to hear owls.