Historical condition
During the 1950s and 1960s, the harvest of polar bears rapidly increased throughout the circumpolar Arctic. In response, the five nations where polar bears occur (Canada, Denmark (for Greenland), Norway, United States, and the former Soviet Union) signed the International Agreement on the Conservation of Polar Bears and their Habitat in 1973 (http://pbsg.npolar.no). As a signatory to this agreement, Canada pledged to protect polar bear habitat, and manage polar bear populations based on the best available scientific data.
Since the International Agreement was signed, many polar bear populations recovered to former levels as harvests were controlled and closely monitored.
 |
| Figure 7. Average body condition index values for Southern Hudson's Bay polar bears captured in Ontario between 1984-86 and 2000-05 (Obbard et al). |
Current condition
The Southern Hudson Bay subpopulation of polar bears is currently estimated to contain between 900 and 1,000 bears. The size of this subpopulation has not changed since the mid-1980s. However, the body condition of these bears has declined. Body condition (defined as the combined mass of fat and skeletal muscle relative to body size) is a measure that’s believed to be a good predictor of polar bear health (Figure 7). Bears from this sub-population are also starting to show trends of declining survival rates. These declines are believed to be due to climate change which results in a shorter period of ice cover in winter. (For more information see climate change section).
Previous page... Annual live cycle | Next page... Factors affecting Polar Bears
