Endangered Owls Need Older Forests, U.S. Says

Federal biologists are convinced that northern spotted owls reproduce only in forests with old-growth characteristics, despite timber industry claims to the contrary, a U.S. Fish and Wildlife Service official said Tuesday.

Spotted owls sighted in forests other than old-growth or California redwoods are mainly individuals that are not reproducing and probably moved there because their previous home was logged, said Ralph Morgenweck, the agency’s assistant director for fish and wildlife enhancement.

Final government maps of habitats critical to the owl’s survival--due next month--will reflect the same basic scientific assumptions the agency has been operating under since the bird was declared threatened in June, 1990, he said.

“We are finding for the most part that the old-growth forests are very important to the reproduction of the owl,” Morgenweck said.

The Fish and Wildlife Service has proposed that 8.3 million acres of Northwest forests be designated as the owl’s critical habitat.

The timber industry and several Northwest politicians have tried to persuade the agency to shrink the area of old-growth forests subject to logging restrictions, based on sightings of spotted owls in younger forests and in stands of trees lacking old-growth distinctions.

“We have been finding individual owls sometimes in second-growth in other parts of the range, but we don’t think they are reproducing. In fact, the data shows they are not,” Morgenweck said.

Scientists suspect that the owls can be observed living in the younger forests for some period of time after leaving old-growth areas because they have a fairly long life span, he said.

Spotted owls do reproduce in Northern California’s redwood forests, which take on the old-growth characteristics at an age earlier than the 100 years typical of the Northwest’s old-growth areas. But the redwoods make up only about 7% of the owl’s range, he said.