NorwayPhoto credit: Morten EkkerPolar bears occur throughout the circumpolar region but are not evenly distributed and do not constitute a single nomadic population. Rather, they occur in 19 relatively discrete subpopulations (geographic areas defined by the IUCN/SSC PBSG with the recently amended Northern Beaufort/Southern Beaufort population boundary; Figure 1). Subpopulation boundaries are defined accord­ing to the best available scientific information and Traditional Ecological Knowledge (TEK) related to the movements and genetics of polar bears, as well as management considerations. For several of these subpopulations, the number of bears is unknown. Based on subpopulation estimates, and presumed densities in areas where numbers are unknown, as of 2015 the IUCN/SSC PBSG esti­mates that there are approximately 22,000–31,000 polar bears across the Arctic.

The current range covered by these subpopulations represents a total land and marine area of approximately 23 million km2. The distribution of polar bears is influenced by the type and distribution of sea ice, as well as the distribution and abundance of prey. Typically, bears spend the majority of their time over produc­tive waters associated with the continental shelf.

09 PB Biology Pop ATTACHSubpopulation map

Polar bear subpopulation boundaries, as of July 2015.

Population Trends and Status by Subpopulation

Determinations of population status and trends for all 19 circumpolar subpopulations are made by the IUCN/SSC PBSG  on an annual basis. The polar bear has been classified as Vulnerable on the IUCN Red List of Threatened Species since 1982. For the latest population figures, please visit the IUCN/SSC Polar Bear Scientific Group webpage.

In Canada, the Polar Bear Technical Committee  assesses the status of the 13 Canadian subpopulations, also on an annual basis.

Source: Circumpolar Action Plan

Habitat Needs and Characteristics

Photo: U.S. Fish and Wildlife ServicePhoto credit: U.S. Fish and Wildlife Service

Reproduction

Photo: Kristin LaidrePhoto credit: Kristin Laidre

Movement and migration

Photo: Kristin LaidrePhoto credit: Kristin Laidre

Diet

Photo: UNEP GRID ArendalPhoto credit: UNEP GRID Arendal

Disease, parasites, pathogens

Photo: U.S. Fish and Wildlife ServicePhoto credit: U.S. Fish and Wildlife Service