International Polar Bear Day - February 27
On thin ice, polar bear image by Pamela Ferris-Olson
Polar Bears International is a non-profit organization with a mission to conserve polar bears and the sea ice upon which they depend. Polar Bear International founded International Polar Bear day 18 years ago as a way to learn and care about the Arctic and polar bears. They chose February 27 for International Polar Bear Day because it corresponds with the time when polar bear moms are hidden in their dens with their new cubs. Researchers say that this period is the most vulnerable time in a polar bear’s life. It is made more vulnerable by the warming of the Arctic reducing the availability of sites appropriate for denning. Fewer places available to den places additional pressure on the survival of polar bears. Cub survival is already tenuous with an estimated survival rate on average of about 50 percent of cubs surviving to adulthood.
Researchers believe around 22,000 polar bears remain in the wild. Polar bears are found only in the Arctic. They live the northern reaches of the United States (Alaska), Russia, Greenland, Norway, and Canada. Canada is home to two-thirds of all wild polar bears. Polar bears are not classified as endangered at this time, but their populations are considered increasingly vulnerable. Climate change is the main factor as it is melting sea ice upon which polar bears depend for hunting their food. Other challenges include increased commercial activities such as oil and gas development, conflicts with people, pollution, disease, inadequate protection of denning areas and seasonal resting areas, and the possibility of over hunting by humans of polar bear due to declining polar bear populations.
Polar bears are considered marine mammals. Their scientific name, Ursus maritimus, means maritime bear. They are the only bear considered to be a marine mammal. They are considered marine mammals because they spend a good deal of time on sea ice hunting for seals, their preferred food. Bears walk across the sea ice and can swim long distances to find food. One documented swim cited a female polar bear swam for nine days straight covering a distance of 426 miles. This long-distance swim is probably out of the ordinary but long swims will become more common as global warming reduces the amount and quality of sea ice.
Pregnant polar bears dig their dens into the snow in the fall, giving birth to their cubs in late December and early January. Their newborn cubs are born blind and weigh roughly a pound, significantly smaller than their mama’s who can weigh up to 500 pounds. The cubs’ coat at birth isn’t dense enough to protect from outside temperatures that can dip below -30 degrees Fahrenheit. A den deep in the snow is an excellent insulator. It shelters the mother and her cubs from the extreme outside temperatures and from outside disturbances. The shelter provides a place for the cubs to grow sufficiently strong to venture on to the sea ice with their mothers in the spring.
Polar bear dens can be difficult to detect. This makes them vulnerable to harm from things like heavy oil and gas exploration equipment and high intensity disturbances such as snowmobilers. This later disturbance will likely to increase as the Arctic warms. Less extreme temperatures will present new opportunities for tourism and development. All these dangers compound the potential for harm to females and their cubs because pregnant and new mothers are reluctant to abandon their dens.
One research team annually studies polar bear denning behavior in Svalbard, Norway. The researchers use remote cameras to capture polar bears as they emerge from their den. They have observed fewer dens and the moms and cubs that emerge from their dens are in poorer condition than in the past. Want to see a video of the maternal den study, click here.
About the artwork. This and other marine animal images by Pam Ferris-Olson can be seen by clicking here. Dancing on Thin Ice depicts a polar bear wearing pointe shoes while balancing on a small section of arctic ice. Polar bears depend upon sea ice to travel, hunt, and breed. The polar bear is possibly the most widely known animal whose fate is associated with global warming. A trend to earlier spring melts and later fall freezes does not bode well for the polar bears’ survival. Cascading in the background are what appear to be Northern Lights but in reality depict the decline of sea ice dating back to 1920 and extending through 2080.
