The use of fire in wildlife management is a controversial area of research. Resource managers are attempting to counter the “Smoky the Bear” image and show that fire can be a valuable wildlife management tool.
So how does fire influence your management area? Wildlife habitat can be positively or negatively impacted by fire. How fire affects an area depends on:
- Fire Frequency: Generally fires are most frequent in grasslands and mountainous boreal forests (lightning). Fire frequency decreases as moisture regimes increase.
- Vegetation Type: Fires can maintain some vegetation types that would succeed to another vegetation type if it did not periodically burn (fire disclimax community). E.g., prairies of the Midwest or moose and willow in the North.
- Fire Intesity: Fire intensities range from cool ground fires (which burn only the litter on the ground) to hot crown fires (which torch and destroy trees).
- The intensity of the burn affects production density and nutrient content of postburn vegetation. It appears that a hot burn will stimulate plant resprouting and increase production and protein levels more than cool burn areas.
- Fire Size: The size of a burn that will produce benefits will vary by area as well as by species of animal.
- Forage and Cover Production: One of the major objectives of using prescribed fire in wildlife habitat management is to increase the productivity of important forages and cover species.
For example, grassland plant production generally increases after a fire. The time of the burning in relation to the stage of plant growth (phenology) and postburn rainfall, have a profound effect on burned grasslands. In woody vegetation, areas where plant succession has advanced, burning can kill the overstay vegetation and set back succession. However, fire can be used to rejuvenate shrubs that have deteriorated from heavy browsing or have growth out of reach for many animals.
Fire has a major effect on nutritive content of vegetation following burning. A fire that reduces or has no effect on production of vegetation may still influence nutrient levels, while a fire that does not affect nutrient content, but does increase vegetation production, may result in overall improvement of forage quality.
The way wildlife cope with fire can vary with species, however most animals escape the ravages of fire and only occasionally are dead bodies found afterward.
- Small Mammals: Small mammals can suffer high mortality but recolonization can be rapid. Experiments have shown that rodents in burrows 2-7 inches underground died only when surface temperatures exceeded 298°F
- Passerines: Burning causes change in vegetation structure and hence changes in bird communities. Generally there is a change in bird species diversity soon after a fire.
- Gallinaceous Birds: Game birds generally respond favorably to fire, depending on the size fo the fire.
- Big Game (mainly deer): Big game are generally thought to benefit from fire, but a wide variety fo responses do occur. Much depends on what conditions occur following fire. Fire also influences big game forage (food) nutrient levels. Food plants that ordinarily receive little use can become more palatable following burning. Also, decadent or old, unproductive plants that are rejuvenated by burning have been shown to be more palatable.
Proper use of fire can be extremely important in retaining and restoring habitat for almost all species. When fire is prescribed to enhance habitat, a knowledge of the animals habitat needs and food preferences are also needed. Generally fire will result in an overall increase in the amount of forage available to wildlife, which can be a very valuable tool for a wildlife manager.