A Good Fire Year for Wildlife

by George Wuerthner

The large blazes that roared through the West in the summer of 2000 matched the 1910 fires that encompassed 3.5 million acres in Idaho and western Montana and catalyzed the Forest Service's strong ethic of fire suppression. And, as in 1910, extreme drought, combined with high winds, drove this summer's fires and made them virtually unstoppable.

Fire suppression and the resulting fuel build-up may have acerbated the situation in some locations, but large blazes are not an aberration as some may suggest. If you take a long-term view, they occur fairly regularly.

Western ecosystems are not shaped by the thousands of small wildfires that ignite annually, but by the occasional large blazes that burn hundreds of thousands of acres. These fires not only play an important role in nutrient cycling and the creation of diverse forest stands, they are largely beneficial to wildlife as well.

Of course, how large blazes affect individual species varies greatly, but as a rule, all wildlife in the West have coping mechanisms that permit them to survive and even thrive in the aftermath of wildfire. I know of no species endangered by large fires, but I know of many threatened by the proposed "cures" for large blazes, such as more logging or livestock grazing.

Despite "Smoky the Bear" propaganda, most wildlife species are not harmed directly by blazes. Big-game animals simply walk away from fires. Birds fly. Small mammals burrow into the soil where the fire's heat cannot penetrate. If a species is harmed, it is usually by habitat losses that may occur the first few years after a fire.

Gains & Losses

This summer's fires may initially cause a slight decline in big-game populations. Forage consumed by fire only exacerbates the more widespread loss in forage caused by the summer's drought, which shriveled up grasses and other plants across the entire region. There may be a major die-off of elk, moose and deer if the next few winters are harsh ones.

But one animal's loss is another's gain. The abundance of carrion or weakened prey will benefit predators and scavengers, from wolverine to grizzlies. Indeed, the winter after the 1988 fires in Yellowstone, grizzlies were treated to a carrion banquet. This summer's blazes will also promote the growth of nutritious grasses and shrubs. Aspen stands will be rejuvenated. The abundance of tender young forage will likely generate an ungulate population boom, which will provide plenty of prey for everything from bears to wolves.

In some parts of the northern Rockies, the recent fires will create a bumper crop of berries like huckleberry. Increased huckleberry production may boost bear numbers and populations of other animals that provide food for predators. At the very least, more and larger berry patches will distribute bears more evenly over the landscape, reducing potential conflicts with humans and other bears.

Improving Habitat Diversity

Big-game animals and other predators may also benefit from burned snags, assuming they are not cut down as part of a "salvage logging" program. As anyone who has ever wandered through a burned forest can attest, standing snags provide a certain amount of hiding cover for elk, bears and other wildlife, certainly more than is available in a logged clearcut. Snags also help "nurse" the regrowth of a new forest, providing some shade and protection from drying winds and alleviating the harshest effects of weather on young trees. Furthermore, as burned trees begin to fall, these tangles of fallen snags impede human penetration and become resting places for everything from big bull elk to bears.

In general, fires burn in a mosaic pattern, with many patches of untouched forest in the midst of charred stands. Regrowing vegetation and fallen trees in burned patches at the margins of unburned forest will nurture an abundance of small prey for mid-sized predators such as lynx and marten.

The abundance of snags also creates fine bird nesting habitat. Some 25% of all bird species in the region are cavity nesters, including a diverse array of predatory species, from woodpeckers to merganser ducks.

Helping Streams & Grasslands

Even aquatic ecosystems may benefit from fires. While during the first few years after a fire there are often declines in aquatic vertebrates due to increased stream sedimentation, slopes are usually stabilized by vegetation within a few years. Then the influx of nutrients released by the fires, combined with fallen snags and other debris that creates new aquatic habitat, typically increases numbers of aquatic insects and fish. More abundant fish means more food for everything from otter to osprey.