FIRE IN CANADA'S NATIONAL PARKS|
Although we do not completely understand ecosystems and their associated processes, we do know that life thrives in a mixed landscape - a landscape with a wide variety of habitats, plants and animals. Waterton's ecosystems have evolved with and have been shaped by fire. This ecological process is as important as water, sun and wind. Many plants have had a long association with fire, so they need it to reproduce and grow well. Fire frequency and intensity (from low to high) will initiate different responses from different plants resulting in a diverse, mixed landscape. Animals reap the benefits provided by diverse plant communities and this is reflected in their numbers, variety, health and distribution.
Just as fires affect the landscape, so can the landscape affect the cycle of fire. Mountains and their associated microclimates have dry slopes, wet slopes and everything in between. As a result, some mountain slopes and valleys are consistently reseeded by fire with lodgepole pine forests and/or grassy meadows, while others may not see a fire for hundreds of years.
Local climates vary as well. For example, we know that since the retreat of the last glaciers (approx. 10,000 years ago) the Waterton Lakes/Glacier area has experienced alternately dry/hot and cool/moist conditions. Six thousand years ago, the climate was hotter and drier, resulting in more frequent forest fires. The prairie expanded while the lower limits of the forests retreated up slope 100 metres (328 feet). The Parks are now experiencing a cooler/moister climate with a more forested landscape.
In addition to natural fires, Aboriginal people traditionally ignited fires to increase prairie grasslands for bison and other game or to clear travel corridors. Early explorers, trappers and trains also started fires. Piecing together Waterton's fire history is a complicated process.
Today, we can't simply "let nature take its course" since wildfires pose unacceptable risks to public safety and facilities. In many cases the only option is prescribed, controlled burns. Ecosystem managers have the task of determining what the historic fire patterns were and what they should be for each of the park's varied habitats. They look at soil layers, fire scars on trees, core samples from lake beds (you would be amazed what is learned from pollen counts sandwiched between layers of mud) and historic photographs and documents.
Managers must also deal with results from past management practices. When Europeans first arrived, they witnessed the apparent devastation of fire. Without knowledge of fire as a natural process, it became their enemy. Fire suppression practices were initiated as early as the late 1800's and became really effective in the 1920's. Ironically, this earlier fire suppression increased the risk of catastrophic fires. Older forests that have not experienced low intensity burns have greater accumulations of fuel (dead wood and under brush). When fires do start they tend to burn more intensely, spread more extensively, cost more to control and pose more of a danger to facilities and fire fighters.
To reestablish more natural conditions, fire is being reintroduced into the national parks. By using prescribed burning, historic fire patterns can be reestablished. This approach is backed by sound scientific knowledge which will incorporate new knowledge as it develops. Fire management involves some risk but these are less than those associated with continued fire suppression. You can only suppress fire for so long until conditions exceed the possibility of suppression and a catastrophic fire can occur. The great fires of Yellowstone National Park in 1988 are a good example.
In WLNP, studies indicate that large, natural fires occurred historically every 100 years or so. Most of these appear to have moved into the park from the west, ignited by lightning strikes at or near the Continental Divide. Fires moving into the Park from the east were mainly the result of the aboriginal practice of setting grass fires.
Waterton Lake's last major fire, in 1935, was caused by a lighting strike up the Boundary Creek valley. Driven by a south wind, the blaze moved along the east flank of Mt. Richards towards the village of Waterton. The fire extinguished itself when the wind switched and began blowing from the North. The young lodgepole pine forests and rich grassy meadows on Mt. Richards and up the Boundary Creek valley, clearly visible from the lake, are a result of this fire.
To date, prescribed burning in Waterton has been restricted to the prairie and aspen forest regions of the park. Native grasses in areas like the Maskinonge and Blakiston fan are being encroached by aspen and willow because of the exclusion of fire (and bison who use to heavily graze and trample aspen and willow). The first prescribed burn occurred in the spring of 1989 and the area recovered quickly with lush vegetation. Burning these areas has resulted in an increase and quality of prairie habitat. This benefits the large numbers of elk that move into Waterton in the winter. In turn, it also benefits predators, scavengers, park visitors and ranchers outside the park who have experienced crop depredation by elk in the past.
Answers to common questions on fire management
- 1. Isn't setting fires interfering with nature?
Landscapes untouched by humans are rare. Even in national parks, ecological processes have been altered by humans and need to be restored. Fire has been suppressed in many parks for decades. Today, we can't simply "let nature take its course" since uncontrolled wildfire poses unacceptable risks to public safety and facilities. Therefore, prescribed fire is used to restore the ecological role of fire.
- 2. Why not log instead of prescribed burning?
Not only is it contrary to park policy, logging offers few of the ecological benefits of fire. It completely removes trees and nutrients whereas fire recycles them. Economically feasible logging requires roads and sorting areas, severely disrupting ecosystems and the visitor experience. In some areas of Waterton, the selective removal of dead trees has occurred to reduce fuel loading and to create fire breaks in and around park facilities (eg. townsite, campgrounds).
- 3. Are prescribed burns a danger to the public?
Fire managers use knowledge of weather patterns, fuel moisture, fire behaviour, natural barriers and effective fire suppression strategies to plan and contain prescribed burns. A program of prescribed fire is safer than suppressing all fire, resulting in unnatural build-ups of fuel and the risk of high intensity fires or letting lightning-ignited fires burn uncontrolled.
- 4. Is the smoke from prescribed burns harmful to health?
Studies suggest that health risks to the general public are very low. Prescribed burns are planned to be carried out in weather conditions that disperse smoke away from developed areas.
- 5. Do prescribed fires cause global warming?
No. Carbon cycles through ecosystems so the CO2 released by fires is balanced by CO2 taken up by plants. Global warming is caused by the addition of excess CO2 from burning fossil fuels.
- 6. What happens to animals in a prescribed burn?
Large mammals are rarely trapped by fire. Spring grass fires are conducted in advance birds' nesting period. Some small mammals and birds may be killed. Over the long term, populations of most species benefit from the habitats created by fire.
7. How much does the fire management program cost taxpayers?
Prescribed burns cost between $20 and $200 a hectare depending on the size and nature of the burn. Fighting wildfires cost $100 to $10,000 per hectare and is not always successful.
Barrett, W. Stephen. 1994. Fire History of Waterton Lakes National Park, Alberta. Parks Canada Contract No. KWL 30004. Progress Report March 1994.
Wagner, C.E. Van. Fall 1995. Research Links. Special Fire Management Issue. Volume 3.Number 2. Parks Canada, Alberta and Pacific-Yukon Regions.
Oliver, Marla. 1995. National Fire Management Message Package. Parks Canada, Heritage Communications.
Peter Achuff. 1995. Ecological Land Classifications. Parks Canada; WLNP; Waterton Alta.
Randell Schwanke. 1995. Fire and Vegetation Manager. Parks Canada; WLNP; Waterton Alta.
If you would like more information please e-mail Parks Canada (Waterton Park) firstname.lastname@example.org Parks Canada - Waterton Lakes National Park main number 403-859-2224
Parks Canada - Waterton Lakes National Park main number 403-859-2224