Volunteers try to preserve burrowing owls on Ore. depot land


PENDLETON — A small band of burrowing owls burst out of the dried grass and sagebrush Tuesday as David Johnson drove along a gravel road on the north end of the Umatilla Chemical Depot.

Johnson, director of the nonprofit Global Owl Project, pulled over and watched as the birds scattered over the scrubby desert. It wasn't long ago that burrowing owls nearly vanished from the depot, casualties of an ecosystem knocked out of balance and habitat that could no longer offer refuge.

Instead, biologists and volunteers came up with a plan to rescue the depot owls in 2008, building artificial burrows where they can nest, roost and hide from predators. The project was an astounding success, Johnson said, and populations are now making an impressive comeback.

Volunteers from across the country returned to the depot Saturday to maintain and upgrade the man-made burrows as part of National Public Lands Day, with Johnson leading the charge. Johnson said they are trying to get as much done as they can before nesting season begins next March or April.

“We've improved our design, so we're trying to upgrade the burrows,” he said. “The depot is decent habitat. It's just a problem with burrows.”

Burrowing owls, distinguished by their longer legs and bright eyes, used to be far more abundant on the depot, Johnson said. That began to change when pronghorn were first introduced to the property in 1959.

The herd grew quickly to 300 head before crashing dramatically, likely the result of inbreeding and outgrowing the limited range, Johnson said. To save their pronghorn, depot officials decided to trap coyotes, which prey on pronghorn calves. However, they also trapped and removed badgers, which burrowed the holes that the owls used to roost.

By 2008, Johnson said they surveyed the land and found only three or four breeding pairs of owls left on the depot. Since putting in the artificial burrows, the population has rebounded to 64 breeding pairs.

“It's been very successful,” he said. “The goal is to develop a source population that feeds the Pacific Northwest.”

Burrowing owls are not endangered in the United States, though Johnson said the birds are losing their Northern range habitat at a rate of 1 to 1.5 percent annually. The birds are listed as endangered in Canada, and are threatened in Mexico.

Don Gillis, who worked as the natural and cultural resources manager at the depot before retiring, said he initially noticed a decline in the number of owls on the property. At first, he couldn't figure out why they were disappearing.

Gillis got in touch with Mike Gregg, a wildlife biologist with the U.S. Fish and Wildlife Service, and they reached out to Johnson, based in Alexandria, Virginia. The artificial burrows were designed by the Global Owl Project, and they recruited volunteers to help put them into place.

Gillis continues to volunteer with the project, and was back with the group on Tuesday. He doesn't want to see the owls forced from the depot.

“That would be pretty tragic,” Gillis said.

There are now 87 burrow sites strategically placed about a quarter-mile apart from each other across the northern portion of the depot, totaling 180 burrows. Johnson said they almost exactly mimic a badger hole, and are located in areas where coyotes and hawks can't sneak up on the nests.

“It's a dangerous world for a burrowing owl,” Johnson said. “Everything wants to eat you.”

The owls themselves eat snakes, mice and insects.

The burrow design uses 55-gallon juice barrels and 10 feet of corrugated plastic pipe, leading from the surface to a chamber about 30 inches underground. A mesh floor also helps to keep pocket gophers away from stealing owl eggs.

Johnson said he would eventually like to reintroduce badgers onto the depot at some point to once again start digging natural burrows, but that proposal has been stalled. He said they will continue to run the man-made burrow project and place small bands onto the young to learn how many of the owlets eventually come back.

“This has become a significant source of research, education and techniques,” Johnson said.

As the Columbia Development works with the Army to obtain and redevelop the land, Johnson said they are also taking an active role in looking at what management practices could be most compatible for both the owls and the community.

“Our agenda is to try and keep them off the Endangered Species Act,” he said. “No one gains from that.”


Information from: East Oregonian, http://www.eastoregonian.com

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