Forest fires are almost invariably described as destructive, even catastrophic. Yet the California forest ecosystems are adapted to recurring fires, and many species depend on fires to create the conditions in which they thrive. What really happens to the ecosystem after a major, high-intensity wildfire? Dr. Chad Hanson of The John Muir Project has been studying this question for years, and he advocates a new paradigm of forest health that recognizes the essential role of fire. His research, summarized in a new book (“The Ecological Importance of Mixed-severity Fires“) challenges some longstanding assumptions about forestry, fire suppression, and post-fire land management.
Dr. Hanson walked us through the post-fire ecological succession, beginning with the beetles who sense the smoke and fly toward the fire! Soon after that, Black-backed Woodpeckers (a rare species that thrives only in recently burned forests with many standing fire-killed snags) arrive; they excavate multiple nest cavities, but only use one, leaving the others available for numerous other species to occupy. Then the wildflowers begin to bloom, drawing insects, which in turn attract more birds and mammals. Meanwhile shrubs and trees germinate and begin growing, providing food for larger mammals (deer, bear) and habitat for smaller ones – which in turn provide prey for predators like Spotted Owls and Pacific Fishers. The net effect is to greatly increase biodiversity and productivity, as compared to a mature forest.
The concept of the “snag forest” (created by fire, drought, or beetles) as a highly-productive ecosystem, on which several rare or threatened species depend, is at odds with the popular perception of the burned forest as a dead landscape – and with public policy. It was shocking to hear that snag forest is actually rarer than old-growth in California.
Complete interview is available on the KZYX Jukebox for the next two months: http://jukebox.kzyx.org/
More links:
EcoWatch article: Don’t Get Burned by Misinformation About Dead Trees and Wildfire
“Fireside Chat” from Geos Institute (Warning: bandwidth-heavy)
Pingback: Fire Ecology – another view | Ecology Hour on KZYX