When barred owls started moving into spotted owl habitat, the U.S. Fish and Wildlife Service initially proposed killing hundreds of the invaders. After an outcry from scientists and the public, wildlife managers instead plan to launch smaller studies to see if culling barred owls prompts the spotted birds to return. Even proponents of the approach acknowledge that the idea raises a thorny question: When is it appropriate to kill one species to help another?
Scientists and wildlife officials have taken extreme measures when species collide. Government marksmen on the Columbia River below Bonneville Dam shoot rubber bullets and explode firecrackers to drive away sea lions fattening up on endangered salmon. Downriver, the U.S. Army Corps of Engineers has been relocating a colony of Caspian terns, which feast on endangered salmon and steelhead. In 2005, government contractors shot Arctic foxes outside Barrow, Alaska, to protect ground-nesting shorebirds. Not long ago, government-sponsored hunters in central Washington killed coyotes that preyed on the world's last remaining pygmy rabbits.
A scientist in California collecting museum specimens recently shot a few barred owls near abandoned spotted owl nests. Two weeks later, a spotted owl returned to the area. "He flew up, sat in the branch and was sitting there, like, ‘Where's my mouse?'" says Kent Livezey, a wildlife biologist with the Fish and Wildlife Service and a member of the scientific work group trying to design barred owl control experiments. "He'd been hanging around."
Joe Buchanan, a biologist at Washington's Department of Fish and Wildlife, advocates targeted hunts if the evidence indicates that culling barred owls creates havens for spotted owls. But he acknowledges there are limits: "We can't push barred owls back to the Mississippi River."
Forsman supports shooting barred owls only to determine a cause-effect relationship between the two birds. Anything beyond that strikes him as impractical. "You could shoot barred owls until you're blue in the face," he said. "But unless you're willing to do it forever, it's just not going to work."
It would be several weeks before Forsman could tell for certain, to his delight, that the pair of spotted owls near Greasy Creek had again defied the odds and reared two young hatchlings. Yet Forsman isn't sanguine about the spotted owl's chances, particularly in northern areas like the Olympic Peninsula, where the barred owl concentration is high. "Whether barred owls will completely replace spotted owls...it's not clear," he says. "I would say the most optimistic view is that at some point we'll end up with a population that's largely barred owls, with a few scattered pairs of spotted owls."
Yet after nearly four decades of tracking these birds, Forsman won't discount nature's capacity to surprise again. "No one really knows how this will play out in the long run," he says. Some elements of life in these ancient moss-draped forests remain shrouded in mystery.
Craig Welch lives in Seattle and is writing a book about wildlife thieves.
Gary Braasch's most recent book is Earth Under Fire: How Global Warming is Changing the World.