It's a warm sunny day in early August and wildlife biologist Eric Forsman heads up to the Willamette National Forest in Oregon's Cascades mountains to climb trees. In this land of 200-foot Douglas firs, Forsman will hoist himself up in a harness to check the nests of red tree-voles, a staple of the northern spotted owl's diet.

From the large tree cavities where spotted owls nest to the decaying logs where they hunt for prey, these birds depend on the lush, old-growth forests of the Pacific Northwest. They are among dozens of species in these ancient forests threatened with extinction, mostly as a result of habitat loss.

But Forsman and his crew of wildlife researchers are reckoning with another threat to the spotted owl: A rival bird getting a critical claw-hold in nesting areas. The barred owl, a larger, brasher, faster-breeding transplant from the East Coast, has invaded the spotted owl's territory, which ranges from Northern California to Washington.

"If you asked me 30 or 40 years ago, I'd tell you that if we just did a good job of protecting old-growth forests, spotted owls would do just fine," Forsman says.

Neglected for years, the northern spotted owl was listed as a threatened species in 1990, after decades of clear-cut logging reduced 90 percent of its old-growth habitat. A landmark 1991 federal ruling forced cutbacks of timber harvests, and the charismatic spotted owl became an icon in a bitter fight between the logging industry and environmentalists.

Lumber mills closed, and thousands of loggers lost jobs in the timber wars, as the Northwest Forest Plan cut harvests on federal lands by 80 percent.

Just as the northern spotted owl seemed spared, it has faced competition from the barred owl, its closely-related cousin. As spotted owl populations have plummeted – by up to 50 percent in Washington in the last 15 years – the number of barred owls has boomed. In some places, according to the U.S. Fish and Wildlife Service, barred owls may have doubled and tripled within 30 years or less.

"The barred owl is throwing a huge monkey wrench into everything – our research and our management of the forests," Forsman says.

To tackle this threat, Robin Bown, a federal biologist with the Oregon office of the U.S. Fish and Wildlife Service, is creating a plan to "remove" barred owls as part of the just-released "revised recovery plan for the northern spotted owl."

The agency is proposing an experiment to selectively take out barred owls, by lethal and nonlethal means, to determine if this would give the spotted owl any advantage. But that's sticking in the craw of some conservationists, birding groups and animal-rights advocates because the experiment alone could mean killing hundreds, if not thousands, of these birds.

Wildlife officials hold out the possibility of capturing and putting the birds in captivity, but admit there aren't enough zoos and refuges for them.

The scientist in Forsman tells him the experiment will be valuable in giving wildlife biologists and land managers better information. But his heart tells him otherwise: "We humans are really good at getting into natural systems and playing God," he says, "often with unpredictable results."

The barred owl removal plan poses an ethical question to the public: Does it make sense to kill some species to save others? At what point should we intervene? Or should we step in at all?

"Such questions often go unarticulated, even though public agencies confront these hard choices all the time," says William Lynn, a bioethicist at Clark University in Worcester, Mass., who was brought in by the Fish and Wildlife Service to convene discussions with stakeholders on the ethical issues.

Even before wildlife officials release their draft environmental impact statement this fall, the controversy is generating hot debate among conservationists, wildlife biologists and animal rights activists.

Argument to take out invaders

The Fish and Wildlife Service postponed acting on the barred owl threat for years, "hoping this would resolve itself," Bown says. But today, "barred owls are moving into spotted owl habitat, taking it from them, and maybe even killing them. If (the spotted owls) don't reproduce, then the next generation doesn't exist."

"We have done 'removals' when we need to save a species," Bown says, citing the National Park Service's program to save the island fox from being killed by golden eagles, in the Channel Islands off California.

"Golden eagles are like owls – big charismatic mega-fauna, too."

In the Channel Islands, the golden eagles took over when bald eagles were decimated by DDT spraying in the 1950s. The goldens pushed the island fox nearly to extinction.

In this successful case, conservation groups, with help from the Park Service, captured 48 golden eagles and released them in the Sierra Nevada. The island fox population rebounded, the golden eagles have not returned and the bald eagle was re-established.

Government wildlife agents routinely cull invasive species thought to threaten native ones in natural settings, from the brown tree-snake that invaded Guam after accidentally being introduced via cargo planes, to the European starling, brought to the United States intentionally by a literary buff so our country would have all the animals found in Shakespeare.

But scientists aren't sure why barred owls expanded their range from the East Coast – whether it is due to humans or just naturally occurring. According to Kent Livezey, in the Western Washington office of the U.S. Fish and Wildlife Service, these East Coast migrants began moving westward more than 100 years ago.

The threat of barred owls is less dire in California than farther north. Still, Livezey recommends controlling barred owls as an "insurance policy" against spotted owl populations crashing.

Dominick DellaSala, chief scientist of the Geos Institute in Ashland, Ore., sees this as a case of "crisis intervention – giving these birds a wing up," particularly in places like Washington's Olympic Peninsula, where, he says, "we could lose all spotted owl during the next few decades."

Lowell Diller, a wildlife biologist for the Green Diamond Co., which owns 400,000 acres of timber adjacent to Redwood National Forest in Northern California, sees it as a clear territorial battle between the birds: "Barred owls tend to be more aggressive. … It's kind of like the rude cousin that shows up at the family picnic and everyone wants to leave!" Of course that's not exactly what's going on, Diller says, "but when these two species interact, they're competing for space."

Diller, a hunter, thinks the removal strategy could keep barred owl populations down. "Nobody thinks we're going to exterminate barred owls, just remove some," he says. "We hunt populations all the time and for food and sport. … This isn't killing an animal for sport, but killing it for conservation purposes."

Letting nature takes its course

Stephanie Boyles, representing the 11 million-member Humane Society of the United States, doesn't agree with scientists who urge experimenting to see if we can help the spotted owl. She questions our ability or even right to do so.

"If barred owls are more fit to live in those areas than spotted owls, and they are able to out-compete them for those resources, is it morally right for us to fight the spotted owl's battle against the barred owl?" Boyles asks. She questions whether the government needs to kill so many raptors – as many as 3,000 over six to 10 years – and recommends studying the owl interactions first.

Among conservationists, there's the worry that barred owl removal is just a distraction from the ongoing job of saving old-growth forest habitat, the No. 1 cause of spotted owl population declines. Some worry that the agency's emphasis on killing barred owls will lead to taking protections away from old-growth forests.

Andrew Orahoske, conservation director for the Arcata-based Environmental Protection Information Center, argues that old-growth habitat is still being overcut, particularly on state and private lands. "Culling barred owls without at the same time increasing protections for old-growth forests is just not warranted and likely will result in a program that commits them to killing barred owls forever," he says.

Ethicists, meanwhile, criticize the idea of human beings thinking we can play God. "Animals are going extinct all the time," says Bernard Rollin, an ethics professor at Colorado State University. "This spotted one just happens to have a romantic aura. Doesn't it strike you as a little crazy that we want to kill the ones with bars, or stripes, because we like the ones with spots better?"

Perhaps, Rollin suggests, evolutionary forces are helping ensure the robust survival of these animals. "What if it turns out this bird is surviving quite well by reproducing with its competitor?"

Ralph Ellis, a philosophy professor at Clark Atlanta University, argues that humans, having degraded these creatures' habitat, are responding wrongly – and too late.

"Having done 99.99 percent of the damage, we find ourselves arguing about the best course of action on the last 0.01 percent," Ellis says. "Perhaps we should instead be more respectful and humble to the animal we've put on the path of extinction, instead of responding by coming out with shotguns."

Back in the old-growth forests, Forsman is asked why owls are portrayed as wise old creatures so worthy of our respect. "Owls are like a bit like us – they have faces, with eyes that look forward," he says, adding, with a touch of irony, "We think they're smart, like us."

Some favor doing everything possible to keep the northern spotted owl from going extinct. Others, however, find distasteful the idea that the federal agency entrusted to protect our wildlife could be killing hundreds of beautiful birds.

© Copyright The Sacramento Bee. All rights reserved.

Francesca Lyman, a Seattle-based freelance journalist, is the author of "The Greenhouse Trap (A World Resources Institute Guide to the Environment)" and "Inside the Dzanga-Sangha Rain Forest" (with the American Museum of Natural History).

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