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.
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.”
According to that line of thinking, the cure — forest thinning and prescribed burning — was worse than the disease.
Megafires are defined as fires that severely burn at least 25,000 acres.
“There is new literature suggesting that even megafires are okay for spotted owls,” says lead author Gavin Jones, a graduate student studying with Peery, “but previous studies were limited because they lacked pre-fire data and had a small sample size of severely burned owl sites, among other reasons. This was a controversy waiting for good data.”
Pre-fire data is a strong point for the new report on the King Fire, which burned in September and October 2014 in the Eldorado National Forest in the Sierra Nevada mountains. The fire, considered one of the largest and most severe in California’s recorded history, burned at the site of a 23 year owl population study. Colored bands on owls’ legs allowed them to be identified from a distance.
Continue reading at the University of Wisconsin-Madison.
Photo: Sheila Whitmore via the University of Wisconsin-Madison.
