Population Growth
Scientist have found 19 populations of polar bears but decided to divide the area into 4 different sea ice regions. Many polar bear populations are little-studied due to the harsh conditions, therefore scientists are able to make informed estimates about the health and condition based on other polar bears in the same sea ice region. The four regions are: Seasonal Ice, Polar Basin Divergent Ice, Polar Basin Convergent Ice, Archipelago Ice.
Seasonal Ice: the southern extreme (Hudson’s Bay). The ice melts each summer and the polar bears must wait for the cold (freezing of ice) so that they are able to hunt again. Polar bears in this area are most affected by the global warming (most endangered) because of the longer ice-free seasons, pushing the limits of their fat reserves. There is approximately 7500 polar bears in this region.
Polar Basin Divergent Ice (Russia and Alaska): the sea ice forms along the shore but then retreats in the summer. As global warming increases, the sea retreats farther which forces polar bears to chose whether they will they ashore and wait for fall and more ice (pushing fat reserves), or swim for long exhausting distances to reach the remaining ice located far offshore. However, ice located far offshore often covers unproductive parts of the sea (not much food) which means that even if the polar bears are able to endure the long swim they may not find any seals to hunt. Those who stay longer ashore have greater risks of human encounters. There is approximately 8500 polar bears in this region.
Polar Basin Converting Ice: Sea ice formed in other parts of the Arctic collects along the shore of these habitats providing polar bears access to seals. Scientist predict that ice in these areas will disappear within 75 years. There is approximately 2400 polar bears in this region.
Archipelago Ice: Islands in the Canadian High Arctic and Greenland that are so north that sea ice remains constant along the coast even in the summer, providing a lot of habitat and hunting opportunities for the bears. There is approximately 500 polar bears in this region (Polar Bears International, 2016).
Seasonal Ice: the southern extreme (Hudson’s Bay). The ice melts each summer and the polar bears must wait for the cold (freezing of ice) so that they are able to hunt again. Polar bears in this area are most affected by the global warming (most endangered) because of the longer ice-free seasons, pushing the limits of their fat reserves. There is approximately 7500 polar bears in this region.
Polar Basin Divergent Ice (Russia and Alaska): the sea ice forms along the shore but then retreats in the summer. As global warming increases, the sea retreats farther which forces polar bears to chose whether they will they ashore and wait for fall and more ice (pushing fat reserves), or swim for long exhausting distances to reach the remaining ice located far offshore. However, ice located far offshore often covers unproductive parts of the sea (not much food) which means that even if the polar bears are able to endure the long swim they may not find any seals to hunt. Those who stay longer ashore have greater risks of human encounters. There is approximately 8500 polar bears in this region.
Polar Basin Converting Ice: Sea ice formed in other parts of the Arctic collects along the shore of these habitats providing polar bears access to seals. Scientist predict that ice in these areas will disappear within 75 years. There is approximately 2400 polar bears in this region.
Archipelago Ice: Islands in the Canadian High Arctic and Greenland that are so north that sea ice remains constant along the coast even in the summer, providing a lot of habitat and hunting opportunities for the bears. There is approximately 500 polar bears in this region (Polar Bears International, 2016).
Based off the latest IUCN (International Union for Conservation of Nature)
report, it is predicted that there are approximately 26,000 polar bears in the world (Polar Bears International, 2016).
Polar bears can be found living across the Arctic. They are abundant in areas with year-round sea ice and seal populations. There are five nations with polar bears: U.S. (Alaska), Canada, Russia, Greenland (Denmark), and Norway (Svalbard). These are divided into 19 sub populations of polar bears, 8 of which are in direct contact with Canada (Polar Bears International, 2016).
Figure 1 shows the 19 sub populations and their estimated polar bear population numbers. Many of these areas are data deficient due to their location and the bears’ constant movement. However, it is estimated that Barents Sea, Lancaster Sound, Foxe Basin and Davis Strait populations are the greatest out of all the subdivisions (World Wildlife Fund, 2013).
Figure 1: Trends in Polar Bear Subpopulations (2013)
report, it is predicted that there are approximately 26,000 polar bears in the world (Polar Bears International, 2016).
Polar bears can be found living across the Arctic. They are abundant in areas with year-round sea ice and seal populations. There are five nations with polar bears: U.S. (Alaska), Canada, Russia, Greenland (Denmark), and Norway (Svalbard). These are divided into 19 sub populations of polar bears, 8 of which are in direct contact with Canada (Polar Bears International, 2016).
Figure 1 shows the 19 sub populations and their estimated polar bear population numbers. Many of these areas are data deficient due to their location and the bears’ constant movement. However, it is estimated that Barents Sea, Lancaster Sound, Foxe Basin and Davis Strait populations are the greatest out of all the subdivisions (World Wildlife Fund, 2013).
Figure 1: Trends in Polar Bear Subpopulations (2013)
Figure 2 depicts the years of abundance of polar bear individuals in each of the 19 sub populations.
Baffin Bay, Chukchi Sea, Kane Basin, Lancaster Sound, Norwegian Bay, Southern Beaufort Sea and Western Hudson Bay populations have shown a decline in bear numbers since their years of abundance.
Davis Strait, Gulf of Boothia, Northern Beaufort Sea and Southern Hudson Bay populations have since remained stable, meaning there has not been a great change in population size.
M’Clintock Channel populations have been said to increase since year of abundance.
Areas including the Arctic Basin, Barents Sea, East Greenland, Kara Sea, Laptev Sea and Viscount Melville have not been actively explored and charted. These areas are in the midst of the arctic where conditions are harsh, making constant Figure 2: Trends in Polar Bear Subpopulations in Years of Abundance
research difficult to conduct
(Richardson & Vongraven, 2011).
Baffin Bay, Chukchi Sea, Kane Basin, Lancaster Sound, Norwegian Bay, Southern Beaufort Sea and Western Hudson Bay populations have shown a decline in bear numbers since their years of abundance.
Davis Strait, Gulf of Boothia, Northern Beaufort Sea and Southern Hudson Bay populations have since remained stable, meaning there has not been a great change in population size.
M’Clintock Channel populations have been said to increase since year of abundance.
Areas including the Arctic Basin, Barents Sea, East Greenland, Kara Sea, Laptev Sea and Viscount Melville have not been actively explored and charted. These areas are in the midst of the arctic where conditions are harsh, making constant Figure 2: Trends in Polar Bear Subpopulations in Years of Abundance
research difficult to conduct
(Richardson & Vongraven, 2011).
Future Trends
Future trends of polar bear populations cannot be accurately noted. Numbers often fluctuate due to multiple human influenced limiting factors. Climate is constantly changing due to the amount of pollution on planet earth. Hunting and oil exploration also predict future trends. Whether or not polar bear populations increase, decrease or remain stable depends on conservation biology and change in humans’ behaviour. However, it is predicted that population numbers will decrease by approximately 30% by 2050 (World Wildlife Fund, 2016).