Forests occupy approximately 40 percent of the vast Canadian landscape, cover approximately 417 million hectares, and constitute ~10percent of the global forest resource. Of the total forest area, approximately57 percent (~235 million hectares) is considered commercial forest, managed fora variety of purposes, including timber production. Approximately 1 million hectares are harvested each year. Canadas non-commercial forest, situatedtothe north, is made up primarily of open forests comprising natural areas of small trees, shrubs and muskeg, and is rich in biodiversity.
Fire is natural to Canadian forests, particularly in the boreal zone (Canada has 30 percent of the worlds boreal forest) which has been shaped by periodic wildfire for millennia, to the point that fire is essential to boreal ecosystem structure and function. Crown fires dominate in the Canadian boreal zone, with the result that tree species have adapted to lethal fire, regenerating from seed released soon after the passage of the fire. Large contiguous areas of crown fire-prone even-aged forest dominate the boreallandscape.
For much of the first half of the 20th century Canadian fire management practices were strongly influenced by European approaches to forest management. Fire was seen as an enemy and something to be eliminated from the forest whenever and wherever possible. Over time there has been a gradual recognition that eliminating fire in Canadian forests is neither economically possible or ecologically desirable. Modern fire management programs in Canada now balance the protection of human lives and property withan awareness and consideration of the natural ecological role of fire.
Canadian Forest Fire Statistics
Forest fire statistics have been archived in Canada since1920 and, within limits, this extensive record permits a general analysis oftrends in this country (Figure 1). However, it is recognized that the Canadian fire record prior to the early 1970s is incomplete, as various regions of the country (particularly in the north) were not consistently monitored during this period. For example, the Yukon and Northwest Territories have only reported burned areas since 1946, while the province of Newfoundland began reporting in1947. It is expected that incomplete records are much more of a problem prior to1950, and the advent of satellite coverage in the early 1970s has resulted in a virtually complete record over the past 3 decades.
Figure 1. Number of fires and area burned in Canada, 1920-1999.
Keeping these uncertainties in mind, fire occurrence in Canada has increased steadily (primarily due to increasing population pressures and forest use) to average close to 9000 fires annually since 1980. The averageannual area burned has increased post-1970, to an average of 2.8 million hectares during the 1990s. Annual area burned is highly episodic and can vary by an order of magnitude (e.g., from 0.76 million hectares in 1984 to 7.28 million hectares in 1989).
Regional-scale lightning fire occurrence varies significantly across Canada, but on average lightning accounts for 35 percent of fires nationally. However, lightning fires account for ~85 percent of the total area burned, largely due to the fact that lightning fires occur randomly and often in large numbers, presenting access problems not normally associated with human-caused fires. The result is that lightning fires generally grow larger, asdetection and subsequent initial attack is often delayed.
There are two primary reasons why the impact of fires onthe Canadian landscape varies significantly at a regional scale:
1. Extreme fire weather/fire danger conditions occur in the boreal forest zone of west–central Canada.
2. Fires occurring in remote or unmanaged forest zones are often allowed to burn in a natural manner.
Sophisticated fire management programmes in all Canadianprovinces and territories are largely successful in controlling the vast majority of forest fires at an early stage, particularly in the intensively protected forest zone. As a result, only ~3 percent of the fires in Canada grow larger than 200 hectares in size, but these fires account for ~97 percent of thearea burned nationally. A large majority of the larger fires occur in thelimited suppression or modified suppression zones of Ontario, Manitoba, Saskatchewan, and the Yukon and Northwest Territories regions where unmerchantable timber values permit more natural fire regimes. An examination of the spatial distribution of large Canadian fires (Figure 2) shows by far the greatest fire activity and area burned occur in the boreal region of west-central Canada. This is due to a combination of fire-prone ecosystems, extreme fire weather (a continental climate), frequent lightning activity, and reduced levels of protection in the region.
Figure 2.Greatest fire activity and area burned occur in boreal region of west centralCanada.
The preponderance of large fire activity in west-central Canada is also reflected in Figure 3. The shortest fire cycles occur in thisregion, particularly in the boreal shield areas of northwestern Ontario,northern Manitoba and Saskatchewan, and the Northwest Territories.
Figure 3. Typical fire cycles in Canada.
Canadian Fire Management Capacity
In Canada, the ten provinces and three territories own the land and are responsible for all land management activities, including forestand fire management. The federal government, through Parks Canada, operates afire management program in a number of national parks across the country. All fire management agencies in Canada are autonomous and have unique organizational structures and approaches.
Fire suppression resources in Canada are shared as required between agencies under the Canadian Interagency Mutual Aid ResourcesSharing (MARS) Agreement, and the Canadian Interagency Forest Fire Centre(CIFFC) in Manitoba coordinates the sharing and movement of resources. Canada also has a reciprocal agreement with the United States that provides for the fast movement of resources between the two countries during severe fire incidents. Canada has a fleet of fifty Canadair CL-215/415 aircraft. These aircraft are operated by the provincial/ territorial governments and were purchased as a cooperative federal/provincial undertaking.
Fire management is a costly undertaking in Canada. Both fixed and variable costs have risen dramatically over the past 25 years, and this trend is expected to continue. At the present time, fire management costsare averaging $500 million CDN annually.
Forest Fire Research in Canada
Canada has conducted a national forest fire research program for the past 75 years. Under the auspices of the federal forestry agency (currently the Canadian Forest Service), this program has traditionally addressed major and topical fire management issues and has evolved in concert with, and in support of, changing fire management practices nationally. Although fire research activities are carried out at academic and provincial/territorial institutions in Canada, research at the federal government level has been dominant, providing the much-needed stability and continuity required to build relevant and adaptable research program. Despite fluctuating levels of funding support and the associated continual opening/closing of research establishments, fire research at the federal level in Canada has endured, building on previous research and producing leading-edge scientific solutions to Canadian fire management problems. A prime example is the Canadian Forest Fire Danger RatingSystem (CFFDRS), developed over a half-century and completed in 1989, now in use throughout Canada and in a number of countries internationally. Canada has also been a leader in the development of computerized fire management decision support systems that have revolutionized operational fire management in Canada,and have been exported extensively.
At the present time, the Canadian Forest Service fireresearch programme has a complement of 25 (16 professionals), located primarilyat the Northern Forestry Centre in Alberta and the Great Lakes Forestry Centrein Ontario, with smaller complements at the Pacific Forestry Centre in BritishColumbia and the Laurentian Forestry Centre in Quebec. Research is primarilyfocused in four areas: fire behaviour/fire danger, fire management systems, fireecology, and fire and global change.
Fire management in Canada has evolved in response to regional and national priorities over the past century. While these pressures are expected to continue, larger international environmental issues are becoming increasingly important. Awareness of the potential impacts of climate change onforest fire regimes at northern latitudes, particularly the circumpolar borealzone, are raising international concerns over the effects of increasing fireactivity on the global carbon budget. Any movement towards warmer and drier spring/summer weather in Canada can be expected to translate directly to more frequent and severe fire activity, with resulting impacts on the global carbon budget. In a post-Kyoto world, Canadian fire management agencies must deal with the impact of increased fire activity on the Canadian forest resource, while at the same time recognizing, and responding to, international concerns over the global implications of changing fire regimes in the carbon-rich boreal zone.
IFFN/GFMC contribution submitted by:
Brian J. Stocks Senior Research Scientist Forest Fire and Global Change Canadian Forest Service Natural Resources Canada 1219 Queen Street East Sault Ste. Marie, Ontario P6A2E5 CANADA Fax: ++1-705-541-5701 Tel: ++1-705-541-5568 e-mail: email@example.com