So far this winter, my wife and I have found three occupied great horned owl nests without getting out of our car.

She spotted one in a thick stand of trees along Interstate 494 in Eden Prairie. I found one along Hwy. 610 in Brooklyn Park. And we saw another along Hwy. 55 in Plymouth that has been occupied by owls for the past three years.

Great horned owls nest well before spring, most often choosing a stick nest used last by a hawk or crow. So, to find a nesting owl, you look hard at large stick nests in deciduous trees, hoping to see the top of an owl head with those two feathered "horns."

Of course, if you're driving, it's best to have a passenger act as designated spotter.

We also may have a pair of owls in our heavily wooded Wayzata neighborhood, but I haven't found the nest yet. These birds will defend a territory as large as 2 square miles. In our neck of the woods, that's more trees than I can handle.

Early nesters

No other bird species in Minnesota begins its nesting season so early. In fact, these birds sometimes have to keep their eggs warm in temperatures that hit minus-20. Why make such a tough job of it? Why don't they wait until the warmer days of spring, like most other birds?

Ornithologists don't know for sure, but they offer several suggestions:

• It's easier to claim a nest when the previous occupants are still down South somewhere.

• By the time the young owls are ready to hunt on their own, the young of the mammals on which they prey will be available. It's easier to practice their hunting skills on prey less skilled in evasion. And although the young owls may hunt on their own by early summer, they'll continue to supplement their catch by begging for food from their parents well into the fall.

• Both the brains and the bodies of great horned owl youngsters take a relatively long time to mature. Because they need to be fully mature to make it through the upcoming winter, hatching earlier may give them a few essential months to mature.

Hunting machines

Great horned owls are uniquely equipped to be hunters. And, if the owl fossils found in the Midwest are any indication, they've been honing their killing skills for about 60 million years.

Great horneds hunt at night. Good thing their vision is 50 to 100 times better than yours at distinguishing small objects in dim light. They have exceptional depth perception. And their hearing is probably better than their sight. Their talons can produce up to 500 pounds of pressure per square inch. Doesn't sound like much? Well, your hands and mine are good for, oh, about 60 pounds.

Their large wings allow them to glide easily and the soft feathers that cover the leading edge of their wings allow them to move silently through the air.

These birds are hunters of small creatures: Rabbits are their preferred meal, but they'll also eat large rodents, mice, voles, ducks, game birds, songbirds, reptiles, fish and amphibians. And they occasionally become meals for their own kind. There is evidence of great horned owls killing and eating other great horned owls.

Great horned owls have few predators, if you don't count us.

On late-winter nights -- when it isn't frostbite-cold -- I'll crack one of our bedroom windows for a few minutes on the chance that I'll hear an owl call. When I hear that deep, rhythmic "hoo hoo-oo hoo hoo," it's a pure, if fleeting connection with an ancient creature that does one thing exquisitely well.

Jim Williams, a lifelong birder, is on the U.S. National Wildlife Refuge Birding Initiative Committee. He also is a member of the American Birding Association, Ducks Unlimited, Pheasants Forever and Delta Waterfowl. Join his conversation about birds at www.startribune.com/wingnut. He can be reached by e-mail at two-jays@att.net.