The polar bear is an iconic symbol of the Arctic environment, existing at the top of the northern food web. Canada holds a unique global responsibility for this species, as the vast majority of the world’s population resides within its northern territories and provinces. Determining the exact number of these wide-ranging marine mammals is a complex undertaking. Establishing an accurate population figure remains foundational for effective conservation and management.
Determining the National Population Estimate
The current consensus estimate places the total number of polar bears in Canada at approximately 16,000 to 17,000 individuals, representing roughly two-thirds of the worldwide population. This figure is not the result of a single, comprehensive census. Instead, it is a summation of individual population studies conducted across various geographic management units. The immense size and remote nature of the Arctic makes a traditional count impossible, forcing researchers to rely on statistical projections.
These national numbers are compiled through international and domestic collaboration, primarily using data reviewed by the Polar Bear Technical Committee. The estimate is dynamic, continually updated as new studies are completed for specific regions. Because the bears travel vast distances, the number is always presented as an estimate with a degree of uncertainty.
Geographic Breakdown of Subpopulations
The national estimate is built from the figures of 13 distinct subpopulations that Canada manages or co-manages out of the 19 or 20 recognized groups globally. These subpopulations are defined by their regional fidelity and are separated by geographic barriers or consistent patterns in sea ice formation. This structure is fundamental to management because the health and trajectory of each group can vary dramatically.
The Canadian bears are spread across three territories and four provinces, with over 90% residing in Nunavut and the Northwest Territories. Well-known subpopulations include those in the Western Hudson Bay near Churchill, Manitoba, and the Southern Hudson Bay, which extends into Ontario and Quebec. Other groups range across the Arctic Archipelago in areas like Foxe Basin and Baffin Bay. Three of Canada’s subpopulations are shared with Greenland and one is shared with the United States, requiring international agreements for co-management.
Scientific Methods Used in Counting
Researchers use a combination of advanced scientific methods and traditional knowledge to obtain population estimates for each subpopulation.
Mark-Recapture Studies
A common technique is the mark-recapture study, where a sample of bears is captured, tagged, and released. Scientists later recapture a portion of the tagged bears and use the ratio of marked to unmarked animals to statistically project the total population size for that area.
Aerial Surveys
Aerial surveys are routinely employed, involving researchers flying over designated areas along specific flight paths, called transects, to count the bears observed. These visual counts are then extrapolated to estimate the total population density.
Genetic Sampling and Traditional Knowledge
Increasingly, genetic sampling is used, where scientists collect hair or scat samples to identify individual bears and estimate population size without physical capture. Indigenous and Traditional Knowledge is also an invaluable source of information. This knowledge provides long-term insights into local bear movements, migration patterns, and denning habits that complement the scientific data.
Current Conservation Status and Trends
The trajectory of the Canadian polar bear population is not uniform, as the fate of the bears is inextricably linked to the sea ice in their particular region. Based on scientific assessments, approximately 54% of the bears are in subpopulations considered stable or increasing. However, about 29% are in subpopulations determined to be declining, with the remaining 17% having an uncertain trend.
The most significant threat is the projected loss of sea ice, which is the primary hunting platform for the species. The Western Hudson Bay subpopulation, for instance, has experienced a rapid decline, attributed largely to the shorter sea-ice season in the southern Arctic. Conversely, some high-Arctic subpopulations, such as those in M’Clintock Channel, have been assessed as stable or potentially increasing.
In Canada, the polar bear is officially listed as a Species of Special Concern under the federal Species at Risk Act. This designation requires the development of management plans to prevent the species from becoming threatened or endangered. This is necessary due to ongoing challenges like habitat loss and increasing human-bear conflict near northern communities.