Early Freeze-Up For Churchill’s Polar Bears?

/ Post by Polar Bears International

Temperatures have plunged into the neighborhood of -20 C near Churchill, and freeze-up has come to parts of Hudson Bay, with polar bears beginning to move out across the ice in some areas — a couple of weeks earlier than in recent years.

We’re cautiously optimistic that the newly formed ice will hold for the Western Hudson Bay polar bears, giving them access to seals after months of fasting. This population has been experiencing longer and longer ice-free periods in recent years, shortening their hunting season.

Scientists have long predicted that less time on the sea ice and less time to hunt would affect the survival rates of polar bear cubs. This has apparently started to happen, with almost no yearling cubs spotted from Tundra Buggies® this year.

Polar bear scientist Ian Stirling, in a Tundra Connections® webcast earlier this week, said the lack of yearling cubs is consistent with the findings from an aerial survey along the western Hudson Bay coast last summer. “Less than 3% of the polar bears counted were yearlings,” he said. “In a normal, healthy population you would expect the yearling count to be from 8% to 12% to 15%. What this says is that fewer cubs are surviving their first year. If that trend continues, the population probably won’t be able to sustain itself.”