Polar bear males are known to kill new cubs in the spring to bring the sows back into estrous. Infanticide is a method of natural selection shared with other large predatory land mammals such as lions. But polar bears living in the Hudson Bay region of Canada may have resorted to cannibalism because sea ice is hardening later each year preventing them from hunting their usual prey--seals. Eight cases of apparent cannibalism by males have been reported to conservation organizations. A retired scientist who studied the Churchill, Canada population for thirty years
says that the number of reported cases is large. The bears of Hudson Bay were forced to wait on shore for four months without food until freeze up. The Bay used to freeze in November, now in early December it is still not solid enough for bears to hunt. In 2004 four bears drowned attempting to hunt on unstable ice.
There are also reports of cannibalism from the Beaufort Sea area in Canada's far northwest corner. Some of the discovered carcasses are adult females which is inconsistent with breeding behavior. The timing of the kills in early December is also inconsistent with mating because female polar bears will not be receptive until spring. The first confirmed cannibalistic killing occurred in 2004 when an adult male was observed attacking a female who had just given birth to cubs in her den. The male dragged her carcass away and partially consumed it. The cubs were killed when the den collapsed from the attack. The impact of climate change on the western Hudson Bay population has been significant according to both the USGS and the Canadian Wildlife Service. There has been a
22% decline in the number of bears at Hudson Bay in the last seventeen years.
US Person is calling for a few climate change deniers to engage in a practical experiment at Hudson Bay. Their results will be shared with his readers which he believes would be much more probative than some imprudent e-mails betwixt frustrated and concerned scientists.
[photo: National Geographic]
Polar bear males are known to kill new cubs in the spring to bring the sows back into estrous. Infanticide is a method of natural selection shared with other large predatory land mammals such as lions. But polar bears living in the Hudson Bay region of Canada may have resorted to cannibalism because sea ice is hardening later each year preventing them from hunting their usual prey--seals. Eight cases of apparent cannibalism by males have been reported to conservation organizations. A retired scientist who studied the Churchill, Canada population for thirty years says that the number of reported cases is large. The bears of Hudson Bay were forced to wait on shore for four months without food until freeze up. The Bay used to freeze in November, now in early December it is still not solid enough for bears to hunt. In 2004 four bears drowned attempting to hunt on unstable ice.