by Steve Sorensen(Originally published in the Warren Times Observer, May 26, 2007.)
Lots of mice and voles find their life's purpose
inside the stomach of a young barn owl.
Maybe it's because we consider owls "wise," or maybe it's because they're silent and powerful, but we humans think we have a close affinity with owls. We do, but maybe not because they're wise or powerful. Maybe it's because they need us and we need them.
I recently had the privilege of learning about one species of owl that most of us have heard about, but few of us have seen. The barn owl (not to be confused with the barred owl) is a "species of concern" in Pennsylvania, and in some states is "endangered." Their numbers are in decline, but research studies are focusing on bringing them back.
Barn owls, as the name suggests, commonly live in barns. Their scientific name is "tyto alba," or white owl, thanks to its pale plumage. Because of its pallid coloration and wavering flight pattern, some people call it the ghost owl. But it's not a hooter. Instead of a spooky "whooo" sound, it makes a raspy screeching noise. They've also been called "monkey face owls" because of the flat, dished, heart-shaped face. It nests in cavities, so a better common name might be "cavity owl," although no one seems to call it that.
Oddly, their ears are asymmetrical. Though not visible, one ear is higher than the other, enabling them to better pinpoint sounds from below as they seek their prey.
Compared to one of its own natural predators, the great horned owl, the barn owl is small. The great horned owl is triple the weight of the barn owl, and the barn owl is no match for it's heavy talons.
Besides predation, one of the big reasons its numbers are declining is because cavities in which barn owls can set up housekeeping are becoming rare. Since long before 1789 when they were first scientifically classified, they've benefited from a close relationship with man, nesting in man-made structures that aren't completely weather-tight. They also nest in dead and decaying trees, so careless forest practices can be a threat to these owls. When hollow trees are cut down, barn owls and other critters lose their home sites.
Old barns are particularly well suited to their needs, because barns host the mice and voles they feed on. Barns also offer plenty of nearby grassland habitat that attracts rodents. Inside a barn, a barn owl will often nest on a hay bale, using its pellets for nesting material. The pellets are the indigestible parts of its prey – tiny bones and fur – regurgitated to provide a soft bed for its eggs.
As old, neglected barns become more decrepit and disappear from the landscape, builders of modern, more tightly constructed barns are encouraged to provide openings on the east side of new barns, away from the prevailing weather patterns, to encourage these handsome owls to take up residence.
In return for shelter, the barn owl keeps the farm's rodent population down, enabling farmers to avoid using poisons. Their chicks eat as many as five rodents per day, and large broods (up to a dozen fledglings) mean lots of mice and voles find their life's purpose inside the stomach of a young barn owl.
To further help the barn owl, some people install structures in trees. You can make a good nesting site by hoisting a 55-gallon drum or a plastic barrel high into a tree, but they're difficult to stabilize. Big wooden boxes make good birdhouses for these big raptors.
If you're inclined to help barn owls in this way, construct your nesting box so the opening faces east and it will be more attractive to the intended tenant. And be sure to build it away from dense woods where the great horned owl lives, and near open fields where plenty of mice and voles will ring their dinner bell.
People who live an outdoor lifestyle -- hunters, hikers, loggers, farmers and others -- should respect and appreciate this beautiful bird, be alert to its needs, and even support programs of study and reintroduction. One program is operated by the Moraine Preservation Fund (www.MorainePreservationFund.org
), which needs volunteers to inventory farms for potential release sites, build nesting boxes, and raise mice to feed owls in the study program.