Mild temperatures this winter is a cause for concern for at least one biologist studying marine and terrestrial mammals in Nunavut.
Reduced snow levels
Wildlife biologist Jeff Higdon says reduced snow levels may cause problems for female polar bears, who need ample snow to dig dens in which they give birth. Research has shown that in important maternity denning areas, such as east Baffin Island, female bears travel to higher altitudes on hills and mountains to find adequate snow depth, stated Higdon.
A reduction in snowfall levels during early winter will potentially reduce available denning habitat for these animals, explained the wildlife biologist.
For polar bears a longer open-water season leads to more time spent on shore. This can reduce seal hunting opportunities for the bears.
Walruses who depend on sea ice as a haul out area are also affected by late freeze ups. When an icy platform is not available, walruses have to resort to haul-out areas on land.
This limits foraging opportunities for walruses, explained Hidgon.
Caribou may potentially be affected by freezing rain. Past events have indicated that caribou may have disappeared and died because of freezing rain. In one extreme case, it is believed the native caribou on Nunavut’s Belcher Islands disappeared in the late 1800s when freezing rain created a layer of ice over all the lichen.
More recently, about three years ago, numerous caribou were found dead by Environment and Climate Change Canada migratory bird researchers on Prince Charles Island in Foxe Basin, Nunavut.
“It’s likely that they died of starvation due to ice cover on lichen forage,” said Higdon.
According to Dr. Stephen D. Petersen, director of conservation and research at Assiniboine Park Zoo, for polar bears, rain on snow may be detrimental. Polar bear dens may collapse, killing the moms and cubs.
However, Arctic animals adapt really well to a fair amount of variation in the weather, said Petersen. Milder weather may be an advantage for some animals since they are not using as much fat resources to keep warm. For example, muskox and caribou may not lose weight as fast.
“There will be winners and losers if the weather in Nunavut is consistently milder. For ice adapted species (ringed seals and polar bears) eventually it will put them at high risk and for other species it might be better (harbour seals and killer whales). It is really difficult to predict what will happen in the short term,” wrote Petersen.
According to hunter Max Kullak, despite the mild weather, the behaviour of animals in Arctic Bay where he lives has not been an issue.
“Hunting is still pretty much the same. Mild weather doesn’t seem to affect their (animals’) way of life and movements,” said Kullak.