ENLARGEA Barred owl is seen at the Miami Science Museum in Miami. To save the threatened spotted owl, the Obama administration is moving forward with a plan to shoot or relocate barred owls, a rival bird that has shoved its smaller cousin aside.
A three-year study released Thursday shows the barred owl is out-competing the spotted owl for resources critical for survival, but does not connect the barred owl to the spotted owl's continuing decline.
The study, conducted by the Oregon State University and the U.S. Geological Survey, monitored interactions between 28 spotted owls and 29 barred owls.
Researchers found the barred owl's larger population and ability to produce more offspring have left the spotted owl losing out on habitat and prey.
Many studies have followed the species separately, but this was the first track them simultaneously, researchers said.
The spotted owl was listed as a threatened species in 1990, causing sharp reductions in logging on federal forests. Recently federal scientists have concluded that barred owls are now on par with logging as a threat to spotted owls.
Geological Survey researcher David Wiens said the new study did not last long enough to determine if the barred owls' growth was contributing to spotted owls' decline.
Researchers reported that barred owls had a 92 percent survival rate each year compared to 81 percent for spotted owls. The barred owl produced six times as many offspring.
Wiens said the study confirmed previous findings that the barred owls is gaining dominance in the Northwest over the spotted owl.
“Pretty much wherever a spotted owl goes, it will encounter barred owls,” he said.
The spotted owl's population has declined by 40 percent over the past 25 years.
Over the past 30 years, the barred owl has expanded its range from east of the Rockies and now overlaps the entire range of the northern spotted owl.
Loss of habitat to logging and competition from the barred owl are the two main threats to the spotted owl, according to federal scientists.
Wiens said the spotted owl's low numbers make competing with the barred owl more difficult. He said there were signs the two species could coexist because the barred owl has a wider range of prey and habitat.
The Obama administration announced in early February it will consider shooting or capturing and relocating barred owls to help the spotted owl.
Douglas County Commissioner Doug Robertson said Thursday he questions the benefits of attempting to rescue the spotted owl if the species may already be doomed.
“If you look at that as a public policy, you can look at how perverse our role is on controlling nature,” he said. “Is our life going to change if we have barred instead of spotted owls in the forest?”
• You can reach reporter Ryan Imondi at 541-957-4211 or by email at rimondi@nrtoday.com.
The study, conducted by the Oregon State University and the U.S. Geological Survey, monitored interactions between 28 spotted owls and 29 barred owls.
Researchers found the barred owl's larger population and ability to produce more offspring have left the spotted owl losing out on habitat and prey.
Many studies have followed the species separately, but this was the first track them simultaneously, researchers said.
The spotted owl was listed as a threatened species in 1990, causing sharp reductions in logging on federal forests. Recently federal scientists have concluded that barred owls are now on par with logging as a threat to spotted owls.
Geological Survey researcher David Wiens said the new study did not last long enough to determine if the barred owls' growth was contributing to spotted owls' decline.
Researchers reported that barred owls had a 92 percent survival rate each year compared to 81 percent for spotted owls. The barred owl produced six times as many offspring.
Wiens said the study confirmed previous findings that the barred owls is gaining dominance in the Northwest over the spotted owl.
“Pretty much wherever a spotted owl goes, it will encounter barred owls,” he said.
The spotted owl's population has declined by 40 percent over the past 25 years.
Over the past 30 years, the barred owl has expanded its range from east of the Rockies and now overlaps the entire range of the northern spotted owl.
Loss of habitat to logging and competition from the barred owl are the two main threats to the spotted owl, according to federal scientists.
Wiens said the spotted owl's low numbers make competing with the barred owl more difficult. He said there were signs the two species could coexist because the barred owl has a wider range of prey and habitat.
The Obama administration announced in early February it will consider shooting or capturing and relocating barred owls to help the spotted owl.
Douglas County Commissioner Doug Robertson said Thursday he questions the benefits of attempting to rescue the spotted owl if the species may already be doomed.
“If you look at that as a public policy, you can look at how perverse our role is on controlling nature,” he said. “Is our life going to change if we have barred instead of spotted owls in the forest?”
• You can reach reporter Ryan Imondi at 541-957-4211 or by email at rimondi@nrtoday.com.
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