Interview: Calculating the End For Hudson Bay’s Polar Bears

No polar bears have been more closely studied than Canada’s western Hudson Bay population. Biologists have compiled an impressive store of data on everything from the weight of females at denning, the decreasing body mass of bears of all sexes, the increasing length of time the bears spend annually on the shores of Hudson Bay, and the decline of sea ice in the bay itself. Now, polar bear biologist Andrew E. Derocher and colleagues from the University of Alberta have marshaled that data to forecast how long it will be before western Hudson Bay’s polar bears disappear. The answer is sobering: With sea ice steadily melting and the polar bears spending less time on the frozen sea, hunting for seals, Derocher and his colleagues recently forecast that western Hudson Bay’s polar bears — whose numbers have dropped from 1,200 to 900 in recent decades — could well die out in 25 to 30 years. Indeed, in an interview with Yale Environment 360, Derocher said that the population — one of 19 in the Arctic — could be gone within a decade if several straight years of low sea ice conditions force the bears onshore for more than five months a year, leading to a sharp decline in the bears’ physical condition. “Changes in this population,” says Derocher, “could happen very dramatically.”

Read the interview