Buffeted by years of logging and the invasion of a tougher owl, populations of the northern spotted owl are falling year after year, despite sweeping protections for the old-growth forests it inhabits. Now, genetic problems are adding to the reasons for worry. A just-released study found the remaining birds are so genetically similar, they are at risk of entering an "extinction vortex."
The northern spotted owl — an endangered icon that spurred a rescue effort so sweeping it brought old-growth logging to a virtual standstill in the Northwest — is now closer than ever to extinction.
Fourteen years after old-growth logging was banned on most federal lands to protect the owls, their numbers are falling year after year.
While there is disagreement over how bad it could get, some are contemplating the virtual disappearance of a bird elevated to sainthood by environmentalists and hung in effigy by loggers.
The situation is particularly bad in Washington, where the rate at which owls are found at nesting sites has fallen by nearly half since 1994. Scientists blame the decline largely on the invasion of a tougher owl and the loss of much habitat to decades of logging.
"It's not looking very good," said Eric Forsman, of the U.S. Forest Service, a pre-eminent spotted-owl scientist. "The populations seem to be gradually going downhill, and it's not clear if or when that's going to stop."
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