Great horned owls
Last updated on Friday, January 03, 2003
Last Saturday, I went birdwatching at the Home Depot store in Las Cruces. We pulled into the store parking lot and headed for the garden section, strolling past potted tomatoes and chile peppers, roses and columbines, and then down an aisle of storage shelves towering high over our heads.
Great Horned Owl Photo courtesy Byron Wright New Mexico Cooperative Extension Service
There, atop a pallet of bagged decorative gravel, on a shelf about twenty feet up, was what we¹d come to see: a great horned owl nest. I saw the fledgling owl first, looking like a shaggy snowman in white downy feathers, except for intense yellow eyes peering right at me.
Then the parent owl looked my way, its huge face seeming very catlike with its smooth plumage, creamy tan and brown markings, and conspicuous tufts of feathers so like ears.
Great horned owls are not easy to hide. They are big birds, standing two feet tall, with wings that measure five feet from tip to tip.
Despite their size, great horned owls are often overlooked because of their camouflaging feather pattern and their ability to fly without making a sound. The forward edge of their flight feathers is serrated to disrupt the flow of air over the wing, thus eliminating the noise created by airflow over a smooth surface.
These birds use their ability to blend in and their silent flight in hunting. A great horned owl watches and listens for prey from an observation perch like the topmost shelf in the Home Depot nursery section, or a treetop, cliff ledge, utility pole, antenna, or building ledge.
Once the owl spots its prey, the bird uses the element of surprise: it swoops down and snatches its meal noiselessly.
Great horned owls hunt prey as small as mice and frogs, and as large as skunks, porcupines, and domestic cats. They have a prodigious appetite: one great horned owl may ingest several mice each night, thus potentially dispatching over a thousand mice each year.
Like most owls, great horned owls are night hunters, prowling for food in twilight or full darkness, and roosting during the day. They are well-adapted to night life: Their eyes are large, and contain a high proportion of light-gathering rods, giving them acute night vision.
The distinctive disk-like arrangement of feathers around their eyes functions much like the radio-antennae that scientists use to hear sound waves from outer space, intensifying sounds and directing them to the bird¹s large ear openings.
Humans can tell whether a sound is closer to their right ear than their left; great horned owls use assymetric ear openings to precisely triangulate the location and distance of sounds, thus enabling them to "see" prey in complete darkness.
Once an owl catches its food, it carries it to a feeding perch, usually in a sheltered location. There the owl fairly inhales its meal, swallowing smaller prey whole, and using its sharp claws to tear larger prey into manageable chunks.
Great horned owls are early breeders, and often begin courting in mid-winter. The male shows the female several prospective nest sites, and the two conduct nighttime hooting duets, before settling down to start a family.
Female great horned owls lay one to six eggs, usually two, and incubate them for around a month. The owlets are born covered with white down, and are fed small mammals and birds by their parents as they grow.
The owlet in the nest I watched looked every bit as big as its parent, but was still downy. They usually acquire their feathers at five or six weeks of age, and do not fly until they are more than two months old.
Great horned owls are among the most adaptable of owls, living in most habitats throughout the Americas, except the tundra of the far north and treeless areas of the Great Plains.
The pair of great horned owls nesting atop the storage shelves at the Home Depot store in Las Cruces is simply taking advantage of a sheltered nesting location, one protected from predators and supplied with night lighting and an abundance of prey. The store, in return, is getting expert pest-removal services. Seems like a great deal to me!