The spotted owl was listed as threatened 17 years ago, but its numbers continue to dwindle through much of its range, federal officials said as they proposed a new plan to prevent them from dying out.
Barred owls have crowded the spotted owls out of prime habitat and, in some cases, attacked them.
A new recovery plan would test weeding out a number of barred owls, a program that has been tested in California.
The recovery plan envisions 18 study areas, from each of which 12 to 32 animals would be removed, lured to their deaths by recorded calls and an owl decoy, then shot at close range.
The barred owl is not native to the West Coast, scientists have said, but followed white settlers across the continent. Controlling the owl is part of a draft plan that covers habitat, research and monitoring.
It would cost $198 million and take as much as 30 years to nurture the spotted owl's numbers to the point at which they could be judged as recovered, the U.S. Fish and Wildlife Service said.
In response to the draft plan, interests in the Pacific Northwest took their usual stances over the resource that's been at issue since the spotted owl became a national environmental figure in 1990: large trees in uncut forests known as "old-growth" where spotted owls live.
An environmentalist who was a member of an advisory panel on the new plan charged that Bush administration officials in the departments of Interior and Agriculture ordered changes that could eventually open larger tracts of old-growth for logging.
"They kind of stood the science on its head," said Dominick DellaSala, executive director of the National Center for Conservation Science and Policy in Ashland. "It's not the best available science."
The Humane Society of the United States called the plan to kill barred owls nonsensical, saying the bird was not the primary threat to the spotted owl.
"The decline of the spotted owl is not due to the barred owls but to the degradation and destruction of old-growth forests" by the timber industry, the society's Lauren Nolfo-Clements said in a statement.
A representative of timber owners and forest product manufacturers said research since the spotted owl's listing has changed assumptions: The bird has more breeding pairs than thought, and needs a variety of forest conditions, not just old-growth, to survive.
"We believe the recovery plan must provide land managers with the flexibility to adapt as habitat conditions change across the landscape," said Tom Partin, president of the American Forest Resource Council, in a statement.
A lawsuit from the timber group led the Fish and Wildlife Service to work on the recovery plan.
The "flexibility" is in an option that would allow local managers of federal agencies to set the boundaries of owl reserves. DellaSala charged that the flexibility was put in the plan on the orders of departmental higher-ups as a step toward doing away with protections for the owl in the Northwest Forest Plan, the Clinton-era document that reduced the cut on federal forests.
Ren Lohoefener, director of the service's Pacific Region, said at a media briefing Thursday he didn't recall who introduced the "flexibility" idea, but said the spotted owl would continue to be protected by the Endangered Species Act.
Interior Department spokesman Hugh Vickery said there was nothing untoward in the work of what was called the "Washington Oversight Committee," including officials such as Mark Rey of Agriculture and Lynn Scarlett of Interior.
He said the Endangered Species Act makes the interior secretary responsible for administering the Endangered Species Act, and it was logical for leaders of the agencies to give guidance.
"There's nothing wrong with that," he said. "That's the way our government works."