Monday, April 05, 2010

British Columbia Spotted Owl Population Critically Low

Pat's Nature News contained a piece of very bad news about Northern Spotted Owls. The species is down to six wild individuals in British Columbia.
Spotted owls live up to 17 years in the wild, but they breed slowly, mating for life and producing just one or two chicks every two years. Silent hunters with excellent vision and hearing, the owls swoop through the open canopy of old-growth forests at dusk to catch wood rats, voles, mice, and squirrels. At one time, at least 500 pairs lived in B.C.’s forests, but over the past 100 years, their habitat has been so heavily logged that the owls have been unable to survive.

Spotted owls are particularly vulnerable to logging because of the way they nest and hunt. The owls don’t build nests but lay eggs in trees hollowed out by age or decay. And when a forest is cleared and prey populations decline, the birds often starve.

The B.C. government is belatedly trying to save the owls, with plans to capture two of the remaining males to breed with two single females in captivity. The government now has 10 owls in its breeding program and hopes to have 30 or 40 pairs so that 70 or so of the birds can be released back into the wilderness in the next decade. Government biologists have also been killing barred owls, which compete with the spotted owls for habitat.
As in the United States, the problem is attributed to habitat loss. Over 70% of the species's habitat throughout its range has been logged. British Columbia's population is much worse off than the one in the U.S. Pacific Northwest, where there is still a viable (if endangered) breeding population in the wild. It also appears from the linked article that the owls in B.C. lack the habitat protections afforded under the U.S. Endangered Species Act. If so, it may be difficult to restart a breeding population in appropriate habitat.