Background

Fire is the primary natural disturbance mechanism in the Northern Rocky Mountains. Fires occur every year in Glacier and did so naturally. Fires vary in severity and in spatial extent. In some years or places, large, stand-replacing fires occur. In other cases, mixed-severity or low intensity fires occur. Most fires create a mosaic pattern composed of burned areas of different fire severities interspersed with unburned portions. In 2003, Glacier had several large fires, each of which created a mosaic pattern. 13% of the park was burned. The length of the fire season and severity of the 2003 fires were record-setting events and yet within natural fire cycles. Because hundreds of organisms in the park have evolved with fire, fire is needed for many of these species to survive and reproduce. Morel mushrooms, Black-backed Woodpeckers, lodgepole and whitebark pines, and wood-boring beetles all benefit from fires and likely benefited from the fires of 2003.

While fires have occurred and continue to occur, wildland fire has primarily been suppressed in Glacier since the park's inception in 1910. With few exceptions, all fires occurring between 1910 and 1991, whether large or small, were actively suppressed with varying degrees of success. Suppression on smaller fires was usually effective, but the effect on larger fires was minimal. Since 1991, prescribed natural fires have been allowed in some cases, but the full role of fire is still restricted. In addition to the suppression of fires starting within the park, many fires that start outside the park and would have entered the park have also been suppressed. Alteration of the fire cycle has altered the prevalence of insects and diseases and the composition and structure of vegetation communities and the animal communities that depend on them. The effect of fire suppression has been most significant in those areas where the historic fire interval was short (e.g., 15-25 years in grassland and ponderosa pine communities). Other forest types, such as cedar-hemlock and spruce-fir, have been less affected because the historic fire intervals are longer (75 to 150 years). Therefore, the natural mosaic and the species diversity normally created by fire are gradually changing, especially in some plant communities.

Other important natural disturbance mechanisms in Glacier are avalanches and floods. Human-induced disturbances include livestock trespass and noise levels created by activities in the park.

Research Needs

Fire

Monitor, assess, and report on long-term fire succession in a wide variety of park habitats. The previous decade of fire on the landscape has provided an unprecedented opportunity to chronicle fire succession.

Quantify fire behavior and effects through research, monitoring, and evaluation in order to manage prescribed fire and refine prescriptions.

Determine avian community response to fire in conifer forests. The unique habitats created by fire are host to a diverse avifauna that changes in composition and relative abundance as post-fire primary succession proceeds in the burned landscape. Document long-term changes in avian communities in burned forests. Examine relationships to different fire severities.

Estimate the effects of recent fires on cavity-nesting birds (especially Black-backed and Three-toed Woodpeckers). Examine habitat selection and partitioning among the species, shifts in nesting densities over time, and correlations between food availability and nest density and success.

Refine the GIS layers for FARSITE fire behavior model. The FARSITE model has proven effective as a viable predictor of fire behavior, given that inputs to the model are well defined. Reliable and accurate FARSITE input parameters are needed for Glacier's landscape.

Assess fire impacts on ungulate winter range. Determine and describe winter range characteristics for whitetail deer, elk, and moose including thermal features on variously aged fairly recent burns. Construct a model of the relationships between forest canopy, snow depth, thermal features, forage, and wintering densities of ungulates. Utilize the model to determine physical and biological changes caused by fire in winter habitats for the three cervid species. Determine the response of winter food supplies to fire.

Update fire history and stand age map. Recent fires since 1994 need to be mapped based on whether they were stand replacement or are now mixed aged stands. Stands without fire evidence should be aged to include their stand age in the database. A fire regime component should be added to the database for each stand. Fuels data collected in recent years should also be incorporated into the database.

Integrate fuels and vegetation mapping. A consistent interagency fuels map and inventory with common classifications and resolutions within ecosystems is needed for Glacier NP. Inventory and evaluate all fire fuels data. Carry out field and mapping efforts to complement already existing data. Use classes that cross walk between agencies. Produce fire fuel maps.

Update the park's stand age map of forest habitats using burn severity data. Conduct multi-year post-fire sampling to refine the ability to project plant succession, or stand impacts, by burn severity classification. Use this information to assist in updating and maintaining fuels data.

Investigate the effects of fire on amphibian distribution and population health.

Natural disturbances

Develop frequency of event analysis and historical record for avalanches, comparing east and west side avalanche cycles.

Map avalanche catchment areas and runout zones according to national standards along US Highway 2 and the Going-to-the-Sun Road. Link an avalanche atlas (above) to this mapping, chronicling the historic record of avalanche activity.

Establish landscape-level disturbance agent and look at drivers; check against Pacific Decadal Oscillation climatic variations and see if it is tied to avalanche response; determine if snowfall level influences the frequency.

Determine the relative amount of woody debris vs. rock material in avalanches. How much woody debris do snow avalanches deliver to the Highway 2 corridor?

Assess plant succession in active avalanche paths through survey and photo monitoring.

Soundscape

Determine the ambient noise levels for selected locations throughout the park to be able to set measurable standards for the protection of natural quiet.

Examine the association between noise levels and visitor satisfaction in relation to expectations for different park zones.

Other human-induced disturbances

Conduct range inventories and analyze trespass routes for trespass livestock from the Blackfeet Indian Reservation onto the east side of the park.