ENJOYING THE OUTDOORS: THE OWLS' SILENT SWOOPS MAKE NIGHT RISKY FOR RODENTS

The original stealth bombers don't target radar installations or missile launchers. They're more apt to rain death upon unsuspecting rodents.

Nature's own design of aerial stealth technology was and is fully functional in owls. Nocturnal predators, owls make a living by surprise attacks on small prey animals. For any of a number of potential victims, doom in owl form can lash out instantaneously on the darkest of nights from seemingly nowhere without a whisper of warning.

The owls that inhabit the region -- the large great horned owl, the mid-sized barred and barn owls, and the compact eastern screech owl -- all have common features. They're built with exceptional night vision and acute hearing for navigation and targeting in darkness, and they're rigged for silent running.

Owls as a group have relatively enormous eyes, and their oversized peepers are the most frontally-located of any birds. The eye position is indicative of a pure hunter. Owls lack the fields of view of many species, but the forward-positioned eyes give them great binocular, three-dimensional vision for precision in targeting prey.

Though they can't see in utter darkness, owls do have good operational vision in light levels so low that humans would imagine it as no light at all. Owl eyes have scads of light receptors which make the most of whatever meager illumination is available. Meanwhile, they aren't blinded by daylight either. Owls can see quite well 24 hours a day, although they are evolved to make their living by night.

To aid those uncanny eyes, owls have acute ears with large openings under their facial feathers. Radar-like hearing helps them detect the faint squeaks of tiny rodents or scratching sounds in the leaves -- signals that area calls to dinner for owls.

complementing owls' sharp senses is the ability to launch attacks on predators on hushed wings. Owl wings are large in relation to body mass, making them easy, buoyant fliers. What's more, their feathers are fringed in ultra-soft, down-like material which cushions the flow of air around those swooping wings.

The result is swishless, muted movement. The stealthy nature of owl wings keeps them from alerting tiny rodents to their approach, for most of the miniature prey animals likewise have keen hearing.

Owl weaponry includes strong gripping and piercing talons, two toes forward and two toes back on each foot. Small victims are pretty much killed on contact. If not, there's always a stout, hooked beak which can finish the job.

Larger prey may be torn apart with the beak, but owls have the habit of swallowing appropriate-sized victims whole. They're not much for chewing.

Perhaps a little offensive at the dinner table, an owl tends to gulp down prey, allow his digestive juices to extract all the good stuff, then ralph back up all the indigestible items in a compact little refuse package known simply as the owl pellet.

Biologists, incidentally, can catalog the feeding activity of an owl by examining the contents of its pellets -- tiny bones, teeth and fur. It's like going through someone's garbage can.

Food sources for owls are rather related to the size of the bird. All of the owls common to the region are heavy users of mice, voles, shrews, birds, frogs and insects such as beetles and large moths.

For the little screech owl, which tops out at a maximum length of only about 10 inches, the miniature critters are about all he can handle. Barred and barn owls, which stretch to about twice the size of screech owls, can deal larger game. They include rats, moles and larger birds.

Great horned owls, which can grow to more than 25 inches in length, are the tigers of the night sky. Along with the micro-rodents and other miniature fare, they are known to kill and devour notably larger prey. Squirrels, rabbits, opossums, waterfowl, young turkeys, domestic cats, barnyard fowl, smaller owls and hawks -- all are potentials for the menu. Horned owls are one of the few predators that seem to be immune to the fragrant defenses of skunks, apparently liking the taste and not minding the smell.

Some expert sources regard screech owls as our most common. However, for my money, it seems that barred owls lead the group in sheer numbers, followed by great horned owls. Barn owls, meanwhile, apparently are comparatively rare.

The regions's four most common owls are rather easily identified by the looks. The great horned owl is unmistakable for its size, being the only large owl with feathery ear tufts. The barred and barn owls are round-headed. The barred owl is somewhat nondescript with its gray-brown camouflage of bars, but the barn owl has a distinctive white, heart-shaped face.

The little screech owl can appear in a gray phase as well as the more common rusty brown, but it's the only small owl with ear tufts or "horns."

From the human perspective, more owls are heard than seen. Their voices are species giveaways, too.

The most heard seems to be the barred owl. He makes a wide range of hoots, screams and whines, but the standard song is the nine-note tune that folk lore describes as "Who cooks for you? Who cooks for you all?" The barred owl is our only owl that ends its hooting with an "aw" sound. More than a few human hairs have stood on end because of some of the barred owl's varied outbursts.

The great horned owl usually isn't as loud, but is lower in pitch with a "Who, hoo-hoo, hoo, hoo" call. Males, incidentally, usually make four- to five-syllable calls, while the female calls more often are six to eight syllables. The girls must have more to say.

The barn owl calls are described as raspy hisses or snores. They apparently don't hoot at all.

Screech owls, one must suppose, screech. Their songs have been described as wavering wails. This is a species of non-hooters, too. One interpretation of folklore is that the screech owl sings "Oh, that I had never been born." I've never exactly heard one say that, but somebody evidently once thought so.

Owls through the ages have in large part been associated with bad news, evil and death. That stems in large part from their mournful, scary-sounding calls in the dark of night.

Aside from a rare chicken-filching, perhaps, owls are pretty much good guys in relation to mankind. They help keep a lot of small disagreeable rodents in check during their nocturnal shopping sprees.

To small critters, those night-penetrating eyes, silent wings and death-dealing talons are quite another matter, however. If you were a mouse scuffling in the leaves in the still of a starlight night, no owl would be on your list of favorite neighbors.

~Steve Vantreese is outdoors editor of The Paducah Sun.