A Tale of Two Kitties

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I've been able to find no explantion, or even mention, of this eerie sound in the books I've consulted. However, a week or so later, Carolyn, out on another of her evening dog trots, spotted two horned owls perched in separate trees on opposite sides of the marsh, screeching at each other exactly as our visitor had scolded me. From those two experiences, we surmise that this weird screeching is a form of close-in communication, and either serves as a territorial proclamation (a caustic warning to interlopers), or has to do with mating.

After such exciting beginnings, I'm hooting in earnest these days.

The great horned owl is the only North American representative of the 12-species genus Bubo, and is closely related to the Eurasian eagle owl ( Bubo bubo ). The great horned owl ranges from Pacific to Atlantic throughout the Americas and from just south of the tundra regions of Alaska and Canada all the way down to southernmost South America. In the lower 48, the horned owl is generally a mottled brownish gray, with a lighter underside and a white throat patch —though it sometimes appears, from a distance at least, to be almost as uniformly white as its north-country counterpart, the snowy owl.

For me, the most fascinating feature of this mysterious bird is its remarkable physical adaptation to life as a winged predator: The great homed owl is a textbook example of the culmination of millions of years of natural selection.

This wide-ranging owl lords it over all other raptors in its territory, and often strikes and carries off prey without ever touching down.

Take, as one illuminating example, the great horny's optical equipment. To begin with, the owl's eyes are outrageously huge in relation to its body size—near the diameter of your peepers or mine, but deeper, more conical, providing increased lens and cornea area for greatly improved night vision. Researchers disagree wildly as to the exact light sensitivity of an owl's eyes, with estimates ranging from a low of 2.5 up to a high of 100 times superior to our own. But no matter the lack of scientific consensus; for all practical purposes, owls truly can "see in the dark." What's more, the owl's eyes are totally functional in the daytime as well, thanks to wide-ranging pupils that open and close according to light intensity, and a translucent nictitating membrane, or inner eyelid, that closes to protect the sensitive retina from extreme brightness.

OWLS

Its head rotates 270°.

As with most predators, the owl's eyes face the front, an arrangement that provides the bird with humanlike binocular vision—an overlapping sight picture that facilitates depth perception. (When you earn your living by rocketing down from the heavens to seize small moving targets, it's right handy to be able to judge accurately when to pull out of your dive and extend your snatching gear.) What's more, the great homed owl can rotate its head an amazing 270°, allowing the big bird to remain essentially immobile while scanning its surroundings for prey.

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