Nature Notes; Burrowing Owls

The barn owl roosts in rafters. The great horned owl seeks the shelter of rocky canyons. But for one owl, the open plains are home.

The burrowing owl is known for its curiosity – and its quirky character. But beyond its clownish reputation, the burrowing owl is finely adapted to the prairies and deserts of West Texas.

With longer legs than other owls, burrowing owls cut an amusing profile. With their families, they chatter and coo. They’ll emerge from their burrows in daylight, to survey the scene. You may catch a glimpse of the owl, raising its rounded head and peering out with its yellow eyes.

Michael Nickell, museum scientist at the Sibley Nature Center in Midland, said he was first charmed by burrowing owls while living in Lubbock.

“You just watch – and they’re kind of comical to me,” he said. “When I was at the Texas Tech museum I’d frequently like to eat lunch outside. And they had this expansive grassy area on the west side of the building, and these prairie dog holes, and when the owls had their chicks, they would pop their little heads up. In my observations they just seem to be curious about life itself.”

Burrowing owls are found in open landscapes across the Americas. There are even populations on islands in the Caribbean. But, historically, the plains of West Texas have been prime habitat for these birds.

No other owl lives underground. Burrowing owls can dig their own holes. But why dig, when you have prairie dogs for neighbors?

“They have the capability to dig their own burrows, provided the soil’s not compacted or too rocky,” Nickell said. “But they usually depend upon a burrow that’s already dug, like, say, an abandoned prairie dog hole.”

Burrowing owls will hunt from dusk to dawn, like other owls. They’ll prey on small rodents from the air. But unlike their owl kin, burrowing owls will also pursue their quarry on the ground.

“One of the most interesting features about them is that their legs are relatively long compared to the legs of other owls,” Nickell said. “That’s an adaptation for running on the ground. Not only can they catch prey on the wing, but also they can run prey down, too.”

Burrowing owls are also set apart by their diet. Insects and plant material are important food sources. The fruit of the tasajillo cactus is a favorite. They feast on grasshoppers, crickets and termites. And the owls have a particularly effective technique for harvesting dung beetles.

“This is one of the most interesting things about burrowing owls,” Nickell said. “Oftentimes just outside the entrance of the burrow, they will collect and accumulate manure, of large herbivorous mammals, like cows. The smell of the dung attracts dung beetles. The owl is essentially having its meals delivered to it. The dung beetle comes to eat the cow manure, and the owl gets the beetle.”

Like a burrowing owl, a rattlesnake will set up housekeeping in an abandoned prairie dog hole. And the owls take advantage of that.

When threatened, the owl makes a snakelike rattle and hiss from its burrow. It scares off predators. Biologists call this type of imitation “Batesian mimicry.”

When white settlers arrived in West Texas, prairie dog towns – a collection of underground homes – stretched from horizon to horizon. Like the bison, prairie dogs were a “keystone species” of the shortgrass prairie – shaping the ecosystem. They had a big influence on what plants and animals could live here.

Prairie dog towns were viewed as hazardous for livestock and horses, and so these rodents were poisoned, trapped and hunted. As prairie dog towns receded, so did burrowing owl populations, Nickell said.

“On the Llano Estacado, wherever we have prairie dog towns, you’re going to find burrowing owls,” he said. “Their population status is largely tied to the population status of prairie dogs. So where war has been waged on prairie dogs, you’re going to find lower numbers of burrowing owls.”

Still, burrowing owls have endured in West Texas. Nesting season begins in late March. This spring, keep your eyes out for these resourceful and fascinating creatures of the plains.

Nature Notes is underwritten by the Dixon Water Foundation and is produced by Marfa Public Radio in cooperation with the Sibley Nature Center in Midland, Texas. This episode was written by Andrew Stuart.Marfa Public Radio logo sibley nature center

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