森林大火威胁斑点猫头鹰的生存
As climate changes and wildfires get larger, hotter and more frequent, how should public lands in the American West be managed to protect endangered creatures that, like the spotted owl, rely on fire-prone old-growth forests? Could periodic forest thinning and prescribed burns intended to prevent dangerous "megafires" help conserve owls in the long run? Or are those benefits outweighed by their short-term harm to owls? The answer depends in part on just how big and bad the fires are, according to a new study.
In a report published Aug. 1 that may help quiet a long-simmering dispute about the wisdom of using forest thinning and prescribed burns to reduce the "fuel load" and intensity of subsequent fires, a University of Wisconsin-Madison research group has documented an exodus of owls following the fierce, 99,000-acre King Fire in California in 2014.
The California spotted owl is a close relative of the northern spotted owl, which became the centerpiece of forest conservation battles in the Northwest in the 1990s. Both owls are indicator species whose presence is said to signify the ecological health of their required, old-growth forest habitat.
As the federal government moves ahead with master plans for 11 national forests in the West, environmental organizations and scientists have been drawn into the dispute, says Zach Peery, principal investigator of the new study, which is now online in the journal Frontiers in Ecology and the Environment. "Proponents of fuel reduction say it's going to benefit the owl by reducing the frequency and size of megafires," says Peery, an associate professor of forest and wildlife ecology, "but there is this body of literature that says the California spotted owl does just fine following severe fires, even when they are large."