Effects of Fire on Alaska's Wildlife and Wildlife Habitat

Perspectives on Fire
Do fires truly "destroy" or "devastate" wildlife habitat as is often reported in the media? Clearly, fire can have negative consequences when it occurs in the wrong place at the wrong time, but these consequences are generally related to humans and are measured in terms of commercial value of forest products or the destruction of personal property. From an ecological perspective, fire generally has positive effects on wildlife habitat and wildlife populations. 

The positive aspects of fire may be at odds with images of Smokey Bear and blackened forests. The effects of fire, however, are temporary. Although uncontrolled wildfires can have extreme effects on wildlife habitats, even these are temporary. In contrast to uncontrolled fires, controlled or prescribed fire is a useful and important tool for land management in Alaska and in other areas of the United States. Nonetheless, a history of powerful images and messages regarding fire as a destructive element are difficult to ignore and have caused many people to question the wisdom of intentionally using fire as a management tool. What effect does fire actually have on wildlife and wildlife habitat?

Prescribed Fire and Land Management
Resource managers in Alaska rely on prescribed fire as an important land management tool. They use prescribed fire to remove combustible vegetation and reduce the risk of uncontrolled wildfire that threatens habitat, human safety, and personal property. By definition, prescribed fires are intentionally started under favorable climatic and environmental conditions and are designed to modify habitat structure, such as reduction of dead spruce trees, without destroying the seed source for important habitat components, like herbaceous food plants.

Don't Fires Harm Wildlife?
Fires certainly can kill animals, but mortality among most species has been found to be minor and fire generally poses no significant threat to wildlife populations. There are a number of factors that influence the extent to which fires cause wildlife mortality including: wind speed, fuel loads, moisture content in vegetation, time of year, size of fire, and others. 

Uncontrolled fires may move much faster and burn at higher temperatures than prescribed fires, posing a much greater risk to wildlife and humans alike. During prescribed fires, however, a greater level of control is exerted over these factors by selecting environmental conditions that minimize risks. 

Various studies and observations suggest fire typically causes little direct mortality to large mobile animals such as Caribou, and bear. Even during the extensive wild fires at Yellowstone National Park during 1988, helicopter surveys revealed a surprisingly low number of deer and other large animals had been killed by fire. Young animals are at greater risk of being killed by fires. But even at young ages, Caribou, Moose and other mammals are highly mobile and have been observed avoiding fires. 

Destruction of bird nests by fire, particularly among shrub and ground-nesting species, is a chief concern of wildlife managers. Attempts to protect nests have resulted in recommendations by some biologists to burn after the nesting season. If their nests are destroyed, however, most birds will attempt to re-nest. Also, prescribed fires typically do not burn entire areas, but result in a mosaic of burned and unburned patches that provide refuge and opportunities for re-nesting amidst regenerating, high-quality habitat.

Using Fire to Manage Wildlife Populations
People often express concerns about the fate of individual animals, while biologists typically discuss wildlife in terms of populations. This is because successful wildlife management focuses on the health of the population, not of the individual. Consequently, wildlife managers support using prescribed fire to promote habitat conditions that result in healthier populations over the long term, even if the temporary effects of fire may result in the death of some individuals. Of much greater influence to wildlife than direct mortality from fire are the effects of fire, or the lack of fire, on habitat quality.

The Post-Fire Recovery Process How Long Does It Take?
Anyone who has observed a recently burned forest or wetland may wonder how long before wildlife begin using what may looks like a charred wasteland. Surprisingly, wildlife begin to use areas immediately following a fire, often literally before the smoke clears. Of course the response of wildlife varies, depending primarily upon the severity and size of the fire. Wildfires that burn out of control in areas with high fuel loads may remove many species of plants and may reduce or delay the extent to which wildlife repopulate the burn site. Periodic prescribed fires, on the other hand, maintain lower fuel loads, typically burn cooler, and may leave more patches of unburned vegetation. These unburned patches of vegetation provide both refuge from the fire and hiding cover during the immediate post-fire recovery process. 

The post-fire recovery process is influenced by fire intensity, type of habitat, and patterns of rainfall. Recently burned areas actually attract many species of wildlife and seem to have little effect on use by others. Tender shoots from resprouting shrubs and herbaceous vegetation that emerge following a fire are highly nutritious and attract Moose and other herbivores. Fruit production is stimulated by fire, resulting in increased availability of seeds and berries that provide food for many species of wildlife. Predators too, are attracted to these areas, presumably in response to the abundance of prey. In general, therefore, fire positively influences wildlife populations in Alaska.

Concluding Thoughts
The rapid recovery of vegetation, the apparent ability for most species of wildlife to use recently burned areas, and the high-quality habitat provided during post-fire recovery suggests that fire enhances habitat for most plants and animals in Alaska. When considering the effects of land management practices, we should ask whether our actions help maintain healthy plant and wildlife populations and conserve the diversity and abundance of Alaskaâs wildlife species over the long term. The information available from research indicates that periodic fires benefit wildlife populations. Fire in Alaska, therefore, represents not devastation, but renewal of wildlife habitats. In many ways fire in Alaska has an effect similar to the coming of spring, both events represent a new beginning for plant communities and for the wildlife that depend upon them.