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The 2008 recovery plan for the northern spotted owl is not likely to help the iconic species recover. In fact, the plan could substantially increase threats to the bird, according to a new study in the journal Conservation Biology.
“The argument used to justify a massive increase in logging under the [spotted owl] recovery program was not based on sound science,” Chad T. Hanson, lead author of the study and a research associate at the University of California at Davis, told the Associated Press.
Hanson is referring specifically to the Bush administration recommendation of eliminating forest reserves throughout more than half of the owl’s range in Washington, Oregon and California. This controversial “thinning” strategy was supposed to reduce growing fuel for wildfires and thereby prevent the destruction of the owl's habitat.
But based on satellite imagery taken between 1984 and 2005, Hanson and his team have found no increased threat of wildfires destroying habitat in the drier regions of old growth forests that the owls call home. The data used to formulate the recovery plan may have produced unreliable results because the information was derived from a smaller swath of forest, over a shorter period of time.
"The existing recovery plan is so clearly based on these incorrect assumptions that you can't just tweak it here and amend it here and fix it," Hanson told the Environment News Service, adding that the occasional intense fire can actually “support peak numbers of wildlife species, including prey species upon which spotted owls depend.”
Not all scientists agree that fires haven’t increased in severity. A study published last year surveyed other images going back to 1972. “If you look at the fire record in the latter half of the 20th century, things start to pick up in the late '80s,” Tom Spies, a researcher with the U.S. Forest Service and co-author on the paper, tells us. “We found a certain amount of fire had taken out a certain amount of old growth.”
The U.S. Fish & Wildlife Service will be reviewing Hanson’s study as they reevaluate the recovery plan. The Obama administration has already announced it wouldn’t defend the strategy. "By July 30 we should know how we are going to proceed," U.S. Fish and Wildlife Service spokeswoman Joan Jewett told AP.
Meanwhile, the numbers of spotted owls continue to dwindle in the Pacific Northwest. A study published in Conservation Genetics in June concluded that a 3 to 4 percent annual drop has led to a parallel reduction in genetic diversity, making the threatened species all the more vulnerable. This “genetic bottleneck” now joins human development, logging and competition with the barred owl as its major threats to survival. Whether wildfires should be on that list is still under fire.
Picture of northern spotted owl from USFS Region 5 via Flickr
