“Waiting for Winter” - Guest Post by Dr. Andrew Derocher / Polar Bears International

The first of our collared females near Churchill swam ashore on July 7^th. For perspective, this is a month earlier than the 1980s. Other bears have trickled to land since. On the break-up side of things, it looks like 2012 is fairly similar to other years since 1998.

The downside is that the frequency of the early break-ups is occurring much more often. Because polar bears “remember” good and bad years by either storing or depleting fat stores over several years, a run of bad years can run down a population. This happens because adult females deplete the fat stores needed to either produce cubs when they’re pregnant or to produce milk when they have cubs. Based on the aerial survey conducted last summer, recruitment of new polar bears in the Churchill area is well below normal now.

What is a polar bear’s life span? In human terms, not very long. In the wild, polar bears live an average 15 to 18 years, although biologists have tagged a few bears in their early 30’s. In captivity, they may live until their mid-to-late 30’s. Debby, a zoo bear in Canada, lived to be 42.

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Guest post by Polar Bears International

June 25^th provided the latest update for sea ice in the Hudson Bay area. The ice is well below normal but better than 2010 and 2011. We know 2011 was a pretty tough year for some Churchill bears and the longer the ice lingers the better.

On a global scale, the ice in in the circumpolar Arctic is still below the 2007 record low. Ice scientists say that warm winds are moving up from southeast Asia and rapidly warming the Arctic. An early snowmelt in much of the Arctic will also add to summer warming. Will 2012 bring a new record low? Stayed tuned. The experts at the National Snow and Ice Data Center in Colorado are not saying how they’ve placed their bets. Of course, this assumes that ice scientists are into betting.

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Guest post by Andrew E. Derocher of Polar Bears International. Read more here.

June 20th definitely felt like summer in Churchill this year when the temperature hit 75 °F (24 °C) and stretched far above “normal.” What this will mean for the rapidly melting ice in Hudson Bay is hard to say, but the ice cover as of June 18th was clearly 10% below recorded coverage between 1981 and 2010.

Here’s hoping for a chilly northern summer, but eastern Canada and the U.S. are sweltering in a heat wave. While it’s not that warm in Churchill, the summer so far is off to a warm start.  It’s a fair bet that polar bears would rather stay at work through the summer – hunting and eating seals is what they’re designed to do. 

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Guest post by Andrew E. Derocher of Polar Bears International. Read more from Andrew here.