Scientists watching spotted owls where barred owl invaders killed
Friday, August 12, 2005
The Seattle P-I
By Jeff Barnard, AP
GRANTS PASS, Ore. -- Federal biologists are getting their first look at whether northern spotted owls will move back into areas where barred owls that invaded their territory have been killed.
Hunters for the California Academy of Sciences have taken three barred owls on the Klamath National Forest as part of a study of how the birds may have changed since migrating across North America and invading spotted owl territory, said Jack Dumbacher, chairman of ornithology for the academy in San Francisco.
The U.S. Fish and Wildlife Service is monitoring the area to see if displaced spotted owls move back into their territory, but has no plans for large-scale killing of barred owls, regional spokeswoman Joan Jewett said.
Dumbacher said he was told by a Fish and Wildlife biologist that spotted owl calls have been heard in former barred owl territories. Jewett said she was unable to confirm that.
Though the academy has permits to collect up to 20 barred owls, it took only three because hunters did not begin until after nesting season, so the birds were dispersed and hard to find, Dumbacher said.
The area east of Yreka, Calif., was home to 32 spotted owls and up to 11 barred owls. The barred owls had displaced two spotted owl pairs and were crowding a third.
The academy will take blood and tissue samples from the birds, check for parasites, and compare their DNA and body characteristics with birds from the East to see if there is some physical explanation for the success of their invasion of spotted owl territory, Dumbacher said. Two birds will be mounted for educational purposes.
The spotted owl became the icon of battles over logging in the Northwest in the 1990s as environmentalists forced the federal government to protect millions of acres of national forests as habitat.
A review of the threatened species status of the spotted owl last year identified the invasion by the barred owl as one of three leading factors in the spotted owl's continued decline, along with timber harvest and wildfires.
More aggressive and adaptable than its cousin, the barred owl apparently hitchhiked West across the Great Plains on forests that popped up because people were controlling wildfires and planting trees around farms, scientists have said. The barred owl arrived in Washington in 1973.
From British Columbia through Washington, Oregon and California, barred owls have been pushing spotted owls out of low-elevation old growth forests along stream bottoms, scientists have reported.
Spotted owls have been finding refuge in steeper terrain at higher elevations, but their numbers continue to decline. Declines have been steepest where barred owls are most prevalent.
Fish and Wildlife recently agreed to go ahead with developing a final recovery plan for the spotted owl, 13 years after a draft plan was put on the shelf. It will be finished within 18 months.
"The barred owl will be a significant factor in the federal recovery plan when they write one," said Steven Courtney, vice president of Sustainable Ecosystems Institute in Portland, a research firm that coordinated the spotted owl status review.
Following a meeting last June in Arcata, Calif., to discuss the threat from the barred owl, Courtney has been circulating a resolution to try to reach consensus on how best to address the barred owl threat. Just what that action will be is hotly debated.
Some timber companies that have been stopped from harvesting timber to protect owl habitat would face fewer restrictions if spotted owls are driven off their lands, but others would face more. Environmental groups are not comfortable with killing one owl to help another.
Some scientists feel thousands of barred owls would have to be killed to keep them from overrunning the spotted owl. Others think such an effort is futile, and it is better to try killing a few barred owls to keep them out of places spotted owls have sought refuge.