U.S. Fish and Wildlife has twice had to rescue ospreys near the McNary National Wildlife Refuge in the last 12 days.
The menace? Baling twine.
About 10 percent of osprey die annually from entanglement, including in scavenged baling twine and fishing line, according to University of Montana research, said Richard Bare, a federal game warden.
In both recent cases near the McNary refuge, ospreys had cushioned their nests of twigs and branches with the colored twine used to bale hay. But later it had tangled around their feet above their talons, tethering them as they tried to fly away.
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Bass anglers reported the first osprey in trouble, Bare said. They had seen a bird -- what they thought was a bald eagle -- struggling at the confluence of the Snake and Columbia rivers.
The osprey and its mate had built a nest high above the water in an Army Corps channel marker that included a platform intended for nesting.
The fishermen could see it trying to fly, flapping its wings about a foot above the nest but unable to rise farther.
After consulting with Blue Mountain Rehabilitation, Bare and biologist Jack Beaujon took a boat out to the channel marker and Beaujon climbed the ladder to the top of the nest about 15 feet above the water.
Osprey pairs usually have one young that survives each year, and as Beaujon worked to cut the trapped bird free from a bundle of twine lining the nest, he was dive-bombed by the other two members of the family, he said.
"They are quite protective," Bare said.
Luckily, they also look out for their own.
If an osprey is trapped and cannot fish, the other osprey typically will feed it, he said.
Bare was concerned the osprey would abandon the nest because of the human intervention, however. Osprey mate for life and often will return year after year to the same nest.
But once free, the bird flew off and started fishing and another was scoping out the nest to make a landing, giving Bare confidence the family will stay at the nest.
Several days later anglers again reported a bird that was struggling to leave a nest, this time just down the Columbia River from the first rescue.
This time Bare and Colby Clevenger, a federal game warden, found a bird tethered by a single piece of baling twine and freed it. They watched long enough to see it return and land on the nest after Bare had freed it.
Eagles won't touch the twine used on hay bales, but "osprey just love it," Bare said.
He recommends that rural residents keep it stored in barrels or barns and that anyone who sees the baling twine or fishing line pick it up to protect osprey.
Anyone who spots an osprey in trouble can call the U.S. Fish and Wildlife Service at 546-8300 during business hours or the Washington State Patrol at 509-575-2320 at other times.