Schriever's green acres 'home on the range' for rare owl species
By Senior Airman Jason Ridder, 50th Space Wing Public Affairs
/ Published July 12, 2006
SCHRIEVER AIR FORCE BASE, Colo. -- Although ground has not been broken on base housing at Schriever, the base is already home to mothers and fathers raising and providing for their families.
Throughout the vast acres of prairie land Schriever sits on is a unique bird that makes its nests underground. Burrowing owls are not capable of digging an entire tunnel so they rely on old prairie dog farms, which they can renovate to suit their needs.
The species is listed as threatened in Colorado and needs help. That's where Leah Smith, a recent graduate of the University of Montana, comes in.
Ms. Smith visited Schriever recently as part of a project that is a joint effort between the University of Arizona and the United States Geological Survey to study the migration pattern of the owls.
She is traveling to Department of Defense lands in Colorado, Nevada, Arizona and southwest California. She catches the owls in humane traps before taking blood samples and feathers. She also weighs and measures the birds, before releasing them.
"Owls have two layers of feathers," said Ms. Smith. "The inner layer develops in the winter, and the outer flight feathers grow in the summer. The feathers have chemical properties unique to the area they were grown in, so using chemistry, we can determine where they spend their winters."
Once scientists know where the birds are spending the winter, they will be better able to protect them.
Trapping owls can involve a lot of sitting and waiting, but the Whitefish, Mont. native doesn't mind.
"I've always wanted to do something in biology," she said. "I started doing work in fisheries but like working with birds much more."
Schriever has plenty of owls for her to study. She has had as many as nine baby owls in a trap at a time, at one of the five areas where the owls have nested. There are also many owls just outside the fence. Ms. Smith said the owls like to make their homes near fences because they can perch on top of them to get a good view of their hunting grounds.
Burrowing owls are small, about nine inches in height with a short tail and long legs. They have yellow eyes, no ear tufts and their faces are framed in white with a black collar.
The owls' breeding grounds span from Canada's southern prairie provinces to areas throughout the western United States including southern California and Texas. In Colorado, burrowing owls are a migratory species, and can be found almost anywhere there are prairie dog burrows from late March or early April through October. In the winter, Colorado owls migrate to Mexico and Central America.
The female will lay from six to 11 eggs, with an average clutch of seven to nine eggs. Both the male and female adults incubate the eggs and care for the young. The young owlets are usually moved to a new burrow two to four weeks after they appear above ground. If they become distressed, they will often mimic the sound of a rattlesnake.
Families usually remain together into September, so even without base housing, some Schriever families will be calling the plains home for a few more months.
(Information from the Colorado Division of Wildlife was used in this article.)