Senior Bush administration officials have reluctantly concluded that saving the Pacific Northwest's rare northern spotted owl from extinction will require the sacrifice of up to 20,000 timber industry jobs, informed sources said yesterday.

An administration task force charged in June with striking a "balance" between owls and loggers has tentatively embraced the main recommendations of a scientific panel that called for preserving large chunks of the ancient, "old-growth" forests where the owls live, sources said.

The decision to follow the panel's basic strategy, albeit with modifications aimed at cushioning job losses, reflects a recognition on the part of administration officials that to do anything less would jeopardize the survival of the bird, violate the federal Endangered Species Act and cause unacceptable political fallout, sources said.

"What has happened is that people have gotten educated about this," said a senior administration official.

The administration's owl strategy, which is not yet final and could be rejected by President Bush, has become a key test of Bush's approach to solving environmental problems. Bush pledged during his election campaign to be "the environmental president," but he also has insisted that environmental protections not impose significant costs in jobs or economic growth.

Nevertheless, the evolving owl-protection plan appears to represent a retreat from the administration's position earlier this summer, when officials indicated that they were not prepared to accept large job losses and suggested that Congress consider revising the Endangered Species Act.

Some administration officials feared that White House Chief of Staff John H. Sununu, who has frequently been at odds with environmentalists, would insist on favoring jobs at the expense of the owls. Earlier this week, several even considered ways to "neutralize" Sununu, perhaps by making a direct appeal to Bush. But Sununu apparently has distanced himself from the decision, sources said.

The owl has become the focal point in a larger battle over the future of the Pacific Northwest's ancient forests, towering stands of spruce and Douglas fir concentrated mostly on federal lands on the western slope of the Cascades in Oregon and Washington. Timber companies prize the enormous trees, some up to 700 years old, for their fine-grained lumber, while conservationists see them as essential to the preservation of wildlife habitat, clean water and biological diversity.

Solving the crisis has caused sharp divisions within the administration and its owl task force, which missed a Sept. 1 deadline for presenting its recommendations and has yet to reach a formal consensus. Task force members are the secretaries of the Agriculture and Interior departments and the heads of the Office of Management and Budget, the Environmental Protection Agency and the Council of Economic Advisers.

Interior Secretary Manuel Lujan Jr. continues to believe that the owl can be saved without causing widespread job losses and is resisting the scientists' recommendations, a spokesman said yesterday.

Nevertheless, sources said that after weeks of deliberations and testimony from outside experts, a task force "working group" has endorsed the scientific panel's recommendations, known as the Thomas report after principal author Jack Ward Thomas, a Forest Service researcher.

These sources said the staff-level, working group members concluded that the Thomas report itself represented a bare minimum for saving the owl, since it would still allow for the loss of up to 40 percent of the estimated 3,000 pairs of spotted owls that remain.

"This . . . was an unprecedented compromise in the conservation of an endangered form of life," said James G. Teer, a former chairman of the wildlife and fisheries department at Texas A&M University and one of the outside experts who reviewed the report for the administration task force. "We should not go any further."

A senior administration official said the Thomas report "will not be shredded" but that steps would be taken to cushion the blow to the timber industry, most likely by phasing in forest protections over several years.

The Northwest timber crisis is driven by the spotted owl's unique need for vast areas -- up to 9,000 acres per pair -- of old-growth forest. The owls nest in the cavities of old, dead trees, and the dense canopy provides shelter from predators.

Thomas's scientific panel, which presented its report last spring, calls for setting aside "habitat conservation areas" of up to 180,000 acres each, creating a kind of owl archipelago in which logging would be prohibited. Trees could still be cut outside the preserves, however, including substantial amounts of old-growth that would not be set aside under the plan.

Only about 2.3 million acres remain of the estimated 25 million acres of old-growth forest that once covered the Pacific Northwest, according to the Wilderness Society, a conservation group whose numbers are accepted by the Forest Service.

Even with the proposed modifications to the Thomas report, "In terms of cut levels, I believe they will be way down from where the industry . . . hoped they would be," said an administration source. The Forest Service has estimated that implementing the Thomas report would reduce the Pacific Northwest timber harvest to 2.6 billion board feet per year, down from a peak of more than 4 billion during the 1980s.

Industry officials have estimated that as many as 150,000 jobs could be lost if the Thomas plan were implemented, but the task force believes the number is far lower -- 12,000 to 13,000 in the near term and up to 20,000 by the end of the century, according to sources. The figures reflect total job losses to the timber industry and in timber-dependent communities.

The task force was appointed in June following the decision by Interior's U.S. Fish and Wildlife Service to list the spotted owl as a threatened species, a step that requires the federal government to develop a recovery plan. Administration officials said at the time that while they wanted to protect the bird, they could not accept the job losses forecast in connection with the Thomas plan.

They said that they would consider asking Congress to modify the Endangered Species Act and raised the possibility of convening the so-called God Committee, a Cabinet-level panel that can grant exemptions to the act in cases of severe economic and social distress.

But the task force appears to have backed away from that approach. As recently as last Thursday, the task force appeared to be moving toward recommending much higher logging levels than implied by the Thomas report, according to a knowledgeable source. This week, however, a consensus emerged that the case for the Thomas report was too strong to "rip it apart," a source said.

At a White House meeting Wednesday night, Lujan, Agriculture Secretary Clayton Yeutter and Bush's domestic policy adviser, Roger P. Porter, discussed ways to preserve essential elements of the Thomas plan while phasing in the restrictions to ease economic hardship in the region, administration officials said.

Administration officials believe that even without the owl controversy, timber industry jobs inevitably will decline, a consequence of automation and other industry shifts, a senior administration official said. In the short term, he said, "You want to sustain jobs and have an orderly transition."

Staff writers Dan Balz and Ann Devroy contributed to this report.