NATURE NOTES:
For Birds of Prey, Winter is the Time in West Texas

By Andrew Stuart

The rains have ended. The weather is bracing. On prairies and grasslands, green gives way to gold. Winter is coming to West Texas, and nature herself seems to quiet and still.

But even as arid months begin, a wave of commanding predators arrives in our region. They are the birds of prey. If you thrill to the sight of a hawk, eagle or falcon above the West Texas landscape, winter is your time.

Kelly Bryan is an ornithologist, and former Davis Mountains State Park superintendent.

“We have a pretty decent contingent of breeding raptors in West Texas,” Bryan said, “but it’s always enhanced every year by hawks and falcons from the north migrating to the Trans-Pecos region of Texas and wintering here.”

It applies to the Llano Estacado as well. In autumn, raptors leave the Rockies and northern Great Plains for warmer climes. Our region is a destination.

Rodents, smaller birds, reptiles – our deserts, grasslands and prairies harbor the prey the need.

Northern harriers travel here from as far as Canada. The male is the “gray ghost.” Don’t look for these raptors soaring aloft. They hunt in low flights, hugging the land.

“The best field mark for a northern harrier is the white rump,” Bryan said. “And they’ve got long slender wings and a long slender tail. The males are almost white. They’re gray and white, so you can tell the adult males. But the immatures and the females are brown. But the best field mark is that white rump.”

The ferruginous hawk is among the most impressive of winter birds, and earns its Latin name – Buteo regalis, the “royal hawk.” With wingspans of up to 5 feet, they can be mistaken for eagles.

They feed on fellow birds – including northern harriers. But mammals are the mainstay. In winter, ferruginous hawks are fixtures above West Texas prairie-dog towns.

Trans-Pecos mountains harbor golden eagles year-round. But across West Texas, populations surge in winter. Golden eagles claim hunting territories of up to 75 square miles. Their wingspans can exceed 7 feet. Silhouetted against the sky, or perched on a pole, a golden eagle is an arresting sight.

But in majesty and stature, they have competition. Bald eagles also winter here. They hunt fish in man-made reservoirs. They also play a role in “cleaning up” West Texas – as scavengers.

“Think about it – we don’t have turkey vultures that winter in West Texas,” Bryan said. “They’re migratory birds here. They leave and go south for the winter. And what fills that niche? Eagles, and ravens.”

Bryan said one winter he saw a dead deer near Valentine– with a bald eagle feeding at one end, and a golden eagle at the other.

Falcons also winter in West Texas. The smallest, with a 2-foot wingspan, is the American kestrel. There is also the prairie falcon – distinctive to western North America. There’s the merlin falcon, dark in plumage. And there’s the world’s fastest animal – the peregrine. For these raptors, other birds are the main prey.

 

Most hawks hunt in open country. The exception are known as accipiters, which include sharp-shinned and Cooper’s hawks. With short, round wings, they weave among trees. They winter in wooded mountains. Or take advantage of urban environments.

Michael Nickell is the Sibley Nature Center’s museum scientist.

“So you often find Cooper’s hawks and sharp-shinned hawks darting in amongst tree branches to go after other birds,” he said. “Sometimes they’ll lie in wait at bird feeders waiting for some finch or something to come in for a meal, and they’ll use the bird feeders kind of as a smorgasbord.”

In addition to the regulars, there are “accidentals.” When winters are especially harsh, northern birds appear far from their typical ranges. Snowy owls have been seen in Texas. Nickell himself identified a northern goshawk in Lubbock County – a record.

Birds are “famous for showing up where they don’t belong.”

“They’ve got feathers, they’re very mobile, and they don’t bother to read the bird field guides,” Nickell said.

Raptors depend on the prey base – a wet summer means more rodents, and more winter raptors.

Our region is home to raptors throughout the year. Red-tailed hawks are common year-round. And Swainson’s, zone-tailed and gray hawks summer here. But when it comes to the number of birds, and the number of species, winter is raptor time in West Texas.