In Charlotte, the barred owls tend to nest in the cavities of the numerous willow oak trees that line the city's streets.
The trees are old and large enough to offer good nesting sites, and the well maintained lawns below provide an open understory—creating perfect conditions for the raptors to hunt.
"The suburban habitat with mowed lawns, azalea bushes, and manicured gardens is really ideal" for the owls, Bierregaard said.
So far, he and his students have found 80 pairs of barred owls nesting in the city over the course of their study.
"There's virtually no place that looks like good habitat for them that doesn't have a pair of owls."
The biggest danger to urban owls seems to be fast-moving traffic: birds flying into cars is the number one cause of death among Charlotte's brood.
But Bierregaard's team has found that a healthy birth rate is keeping the owl population steady.
Scott Terrill is a biologist at H.T. Harvey and Associates, an ecological consulting group based in Los Gatos, California.
"Actually barred owls are doing really well everywhere," he said. "They've expanded their range tremendously in recent years."
Although the owls were traditionally found in the east, they have rapidly extended their range in the last several decades , moving north into Canada and west into California, Oregon, and Washington.
In some places where the barred owls have moved in, conservationists are worried about the effects their invasion might have on native species.
For example, surveys show that barred owls are interbreeding with the endangered northern spotted owls in the old-growth forests of the U.S. West Coast.
This creates sterile hybrids, hampering the endangered bird's reproductive success.
But the people of Charlotte have no qualms about their new neighbors.
"People love 'em," study leader Bierregaard said. "They're big and noisy and they're tame as can be."
The baby owls, he added, make a cute sight splashing around in peoples' birdbaths.
And with expanding human populations, the barred owl isn't the only country bird making a home for itself in cities.
"There seem to be a number of owl species that adapt quite well to urban areas," New Mexico State's Desmond said.
Great horned owls and screech owls are already very common in cities.
The ornithologist has even found burrowing owls nesting in roadside gutters in her hometown of Las Cruces, as well as sawhet owls wintering in downtown Manhattan.
"Because these birds are nocturnal," she said, "they're there, but you just don't notice them."
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