This summer we have had more fires than we can handle. Chetco Bar. Miller Complex. High Cascades Complex and others. The air has been thick with smoke with little relief. No matter which way the wind blew, we tasted the smoke. Eyes watered, and a nasty cough often followed.
Humans have suffered, but how have birds been affected? The good news is that most birds conclude their breeding efforts by about the 4th of July. Some, however, such as robins and song sparrows often have a second or third brood taking them into late July and even August when the fires were strongest, making them vulnerable.
Birds are more mobile than most other animals, and many can move on. Still, there is mortality. Nonmigratory, territorial species such as owls and some sparrows are undoubtedly more strongly affected.
For the nonmigratory species that can get out of immediate harm’s way, there is the problem of finding space that is not already occupied by others of their kind. Populations must adjust to available space and other resources. There will be winners and losers.
There will be further loss long after the fires are out. Forest-dwelling migrants returning to breed next spring will find less habitat available. There will be competition for space with more winners and losers. Hopefully other areas recovering from fire and timber harvest years ago will provide new habitat buffering some of the impact.
In the immediate aftermath of a fire, few species gain from the disturbance. Black-backed and three-toed woodpeckers are two. Following an intense fire, wood-boring beetles are attracted by the chemicals released by the damaged trees. Recently dead and dying trees provide a bonanza for these insects, and these woodpeckers gather from miles around. How these wanderers locate newly burned areas from great distances with amazing efficiency is not clearly understood. The first couple of years after a stand-replacing fire, these woodpeckers feast on the young beetle grubs feeding and growing under the bark and in the wood. This flush of rich food does not last long.
As an ecologist, I take a somewhat longer view. Burned areas recover. Forests will return in time. Madrone, oak and poison oak are some of the first to recover, resprouting from energy stores in the roots. Whiteleaf manzanita and buckbrush sprout in profusion from a seedbank lying dormant in the soil. The resulting brushy habitat provides new habitat for a different set of species. Spotted towhees, green-tailed towhees, fox sparrows, lazuli buntings, MacGillivray’s warblers and house wrens, to list a few, all benefit.
As the conifers regain a foothold, other species find new opportunities, such as black-throated gray and Nashville warblers. In time the hermit warblers, hermit thrushes and Pacific slope flycatchers will return. Every change in nature — and nature is always changing — benefits some species while harming others. This all falls under the heading of biological succession.
In recent years, the number and size of stand-replacing fires has increased. As the climate changes, the habitat that returns after a fire may have a new character and composition, being more similar to those now present in Northern California. Chaparral shrublands may also expand at the expense of forested habitat. There will be losers, but the winners may include a few more birds currently confined to California, including California thrashers, Lawrence’s goldfinches and Nuttall’s woodpeckers.
— Stewart Janes is a biology professor at Southern Oregon University. He can be reached at email@example.com.