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Yet the protection would prove insufficient. Throughout their range, from Canada to California, Northern spotted owls are disappearing three times faster than biologists had feared. Populations in parts of Washington are half what they were in the 1980s. So few birds remain in British Columbia that the provincial government plans to cage the last 16 known wild spotted owls and try to breed them in captivity. "In certain parts of its range," says Dominick DellaSala, chief scientist of the National Center for Conservation Science & Policy, "the spotted owl is circling the drain."
Barred Owls, meanwhile, are thriving. Farther south in the Oregon woods, I crunched through dead leaves behind Robert Anthony, a U.S. Geological Survey biologist, and David Wiens, a wildlife science graduate student at Oregon State. Wiens swept an antenna through the forest, weaving it in and out of snarled branches below overcast skies. Within minutes he pulled up short. The source of his signal looked down from upslope—a barred owl. He'd outfitted the bird with a transmitter the year before.
Half a dozen years earlier, Wiens whispered, spotted owls occupied this patch of forest. "Then barred owls were found and they've kind of taken over," he said. Spotted owls have not been seen here since.
Most of the evidence that barred owls are harming spotted owls is circumstantial; that's why Wiens and other researchers traipse the woods daily, studying how the two species fight for space and food. Still, the trend is clear. Rocky Gutiérrez, a University of Minnesota wildlife biologist, wrote in 2006 that "despite the paucity of information, many biologists now feel that the barred owl is the most serious current threat to the spotted owl."
Both barred and spotted owls, along with great gray owls and rufous-legged owls, belong to the genus Strix, medium-sized birds that lack the hornlike tufts of ear feathers common to many other owls. They are so closely related that they sometimes crossbreed, blurring species boundaries and diluting spotted owl genes. More often, though, when barred owls move in, spotted owls just disappear.
Where spotted owls are finicky eaters, barred owls consume almost anything, including spotted owls. Barred owls, typically 20 percent larger than their rivals, may take over spotted owl nests or slam into their breasts like feathery missiles. "The barred owl is the new bully on the block," DellaSala says. A few years ago, a naturalist in Redwood National Park observed the aftermath of a murderous encounter: a barred owl with a tuft of mottled feathers clinging to its talons flapping near a decapitated, partially gnawed spotted owl. When scientists dissected the spotted owl's body, they saw that it had been sliced and perforated, as if by talons.
No one knows precisely why the bigger birds came West. Barred owls originally ranged from Florida to Maine and west to the treeless expanse of the Great Plains. Sometime in the 20th century, the birds skipped west, possibly across Canada. Perhaps they followed settlers who suppressed fire, allowing trees to grow and providing nesting pockets. Some scientists blame the influx of barred owls on climate change; a few suggest it's a natural range expansion. In 1990, barred owls in a forest west of Corvallis, Oregon, occupied less than 2 percent of spotted owl sites; today, barred owls nest in 50 percent of them. Barred owls have yet to saturate Oregon and California, but in a part of Washington's Gifford Pinchot National Forest set aside for the smaller bird, barred owl nests outnumber spotted owl sites by a third. When barred owls invaded the Olympic Peninsula, spotted owls moved to higher, steeper forests with smaller trees and less food—"like moving from the Sheraton to some dive motel," DellaSala says.
To count owls, which are nocturnal and hard to find, researchers do a lot of hooting; when the birds call back, biologists plunge into the forest toward the sound, usually at a sprint, stopping every so often to call out and listen again, the hoots echoing back and forth through the woods until human and bird wind up face to face. For spotted owls, the sound is vaguely like a cross between a muted rooster call and a French horn: "hoot-hootoot-hoo." For barred owls, the tone is similar but the call is longer and patterned differently: "hoot-hoot-wahoot, hoot-hoot wahoo." For a time, some researchers hoped that spotted owls were just clamming up around barred owls and there were actually more than they thought. But that hope has largely faded. "There's evidence that spotted owls decrease vocalizations in response to barred owls," says Forest Service biologist Stan Sovern. "But honestly, I don't think spotted owls can just be silent somewhere and stay there. Part of their natural history is calling back and forth to one another."
Predictably, perhaps, loggers, timber companies and politicians seized on the barred owls as evidence that logging wasn't to blame for the spotted owl's plight. They have called for a return of chain saws to federal woods, so far without success. But years of efforts by the Bush administration to jump-start logging in the Pacific Northwest remain the subject of courtroom skirmishes between the timber industry, conservation groups and several federal agencies.
Yet far from saying that the logging restrictions were a mistake, owl biologists largely insist that more forests must be spared, especially since heavy logging continues on state and private land. As Wiens and I peered across a timbered ridge, craning to see the barred owl's nest, Anthony said, "If you start cutting habitat for either bird, you just increase competitive pressure."
Related topics: Owls Hunting Environmental Preservation Oregon Forests
Additional Sources
A Conservation Strategy for the Northern Spotted Owl: Report of the Interagency Scientific Committee To Address the Conservation of the Northern Spotted Owl, published by the USDA Forest Service, Bureau of Land Management, Fish and Wildlife Service, National Park Service, 1990


Comments
Interesting how nature can throw us a curve ball. Great pictures too.
Posted by thelma w gannon on December 25,2008 | 03:26AM
The barred owls slowly and steadily came west along the southern edge of the boreal forest in Canada...just look up the observation records there over a series of decades. They have then progress south here on the West Coast. Why does this article again repeat the meme that they may have skipped across the Great Plains?
Posted by west on December 30,2008 | 01:07PM
As a forester I call for NSOs and love to find them even when it makes my timber harvests more complex. It saddens me to see barred owls displacing NSOs in forests where loggers and NSOs have coexisted for many decades. To elaborate on the connection between logging and the NSO, I would like to make the following points. NSOs may prefer old growth type forests and trees but this is unclear since the majority of NSO studies have been conducted in parks with old growth. Certainly, many spotted owls are thriving in second growth forests. Barred owls are much more dependent on old growth. Responsible, sustainable logging can and does happen in tandum with protection of spotted owls. With fire suppression, required foraging areas for NSOs, are less abundant. NSOs frequently move adjacent to openings created by logging for foraging oportunities. The timber industry has come a long way since the report you cited from 1990. It would be nice to see more balanced reporting in this prestigious publication.
Posted by Harlan Tranmer on December 31,2008 | 01:42PM
"bully" "invader" "murderous" "feathery missile" Poetic license notwithstanding, Smithsonian really should keep an eye on its writers' absurb anthropomorphisms. It diminishes science in general and confuses our understanding of natural processes.
Posted by Sydney Brillo Duodenum on January 7,2009 | 05:38PM
As humans, we have a duty to protect the enivironment from ourselves as we do our best to co-exist with it; however, when cases like this where a stronger, more "fit" animal comes along and causes the extinction of another animal it is simply natural for this to happen. To me, targeted hunts are ethically similar to the destruction of habits for timber. We need to protect habitats but also not interfere with the natural order of things even if that the extinction of some animals.
Posted by Zach Blake on January 9,2009 | 06:20PM
Of course they don't want to kill barred owls. The newcomer has provided more leverage in this "managed crisis" The plan is to keep the spotted owl at extinction levels (guess who's counting the owls?)to maintain control over federal forests. I've seen several spotted owls, and they were all in 2nd+ growth forests. These are wild animals with a built in ability to adapt. When are we going to realize that we can't freeze time in the moment when we thought it was best?
Posted by Nikole Jacoby on January 9,2009 | 09:10PM
As a retired BLM wildlife biologist, it was my pleasure to work with Dr. Eric Fosrman for over thirty years. From 1975 through about 1995, I worked primarily on Spotted owls but had opportunity to work with other noted individuals on everything from small mammals and birds to fungi and vascular plants. What this has shown is that the importance of the remaining old growth, virgin forests of the northwest cannot be overstated. This importance has been eclipsed by a single species focus on the spotted owl. These forests gave us taxol, a anti-cancer drug found in the bark of the Yew tree, very few of which existed outside of the natural, native forests, or second growth. At present, work on several species of fungi show promise as anti-inflamatory drugs and one species in particular has been effective in controlling several strains of tuberculosis bacteria. To date, very little of the biological resources found in the native forests have been screened. To lose the remnants of remaining native forest would be a travisty to mankind, not just the timber industry.
Posted by Gerald Mires on February 1,2009 | 03:39PM
thank this help me alot on my history project obout the spotted owls
Posted by patty on April 15,2009 | 03:10PM