Polar Bear Blog – Hudson Bay Sea Ice

Sea ice is rapidly declining across the arctic and many bears are ashore for another season, up to 40% of the world’s polar bears spend some time on shore through the year.  Overall, arctic sea ice is below the 30 year average but above the record lows of late.  Regionally, this means a lot of things, Russian bears as usual seem like they are in tough once again, Southern Beaufort bears could have some long swims ahead of them.

On the other hand, Baffin and Hudson Bay bears are looking to have a pretty fine year.  NSIDC sea ice reports show ice in these regions to be well above average, great news for bears in general.  Just the fact that there seems to be an extra half million square kilometres of sea ice hanging around at the end of July is, well, really something!
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Of course, nothing is as simple as charts, maps and media make them out to be…   Off-hand, these ice charts look indicate that Southern Hudson Bay, Foxe Basin and Davis Strait polar bear populations are having phenomenal years.  In the map above, the red ice (90% concentration) are gathered in key areas for these bears… roughly the Belcher Islands (SH), Southampton Island (FB) and Pangnirtung/Iqaluit (DS).  Beyond that, ice conditions have still been favourable for Churchill’s bear (Western Hudson Bay) and near Qikiqtarjuaq (Baffin Bay).

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That being said, all bears are different.  A mother and cub are hanging out at Eskimo Point near Churchill, off the ice somewhat early.  Several bears have been spotted near Seal River Lodge, north of Churchill.  These bears would have lost a week or two of hunting by swimming ashore that far north.

This really illustrates how difficult life is for bears in the wild, each spring each bear must decide whether to ride the ice south for a few extra seals or swim ashore early, returning to familiar territory.  Females generally pick the latter, preferring a bit more of a conservative survival strategy.

This season reminds me of a late ice season (2005?) where a lot of ice remained well into the summer and well south of Churchill.  This heavy ice year occurred just after the ‘climate change/el nino years’ (roughly 98-2002) where the bear population was devastated.  Anyway, the bears took this opportunity to extend their hunting season well into the summer and ended up well south of Churchill.  What this meant for Churchill was a very late start to ‘bear season’ in the fall, the bears were in good condition, far south and just didn’t ‘need’ to get back to Cape Churchill.  There were almost no bears around until November that year.

It also may have been a real catalyst for the movement of Churchill’s biggest bears to southern Hudson Bay/Kaskatmagan region.  There is evidence that the largest males are staying south of the Nelson River, maybe sitting out the chaos of helicopter research and tourism or just too lazy to walk north… hard to say.

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Usually when its a good ice season in the eastern Arctic, its a tough ice season in Svalbard and Alaska, just the way the jet stream usually works… but the chances of bears making a record dive in Hudson Bay this year are pretty slim.  Most are likely too fat to dive more than a few seconds, bobbing back up like a cork.

When it comes down to it, there’s no real way to spin this year as a bad year for Hudson Bay.  The bears of western Hudson Bay have had the toughest season of the three population in the bay and they still had a very nice hunting season.  Its really looking more and more like this population could not just be stable but increasing…

Great news but as always challenges lie just around the corner.  The ‘blob’ remains in the Pacific and conditions are looking like another El Nino is starting to form…  stay tuned.

 

4 thoughts on “Polar Bear Blog – Hudson Bay Sea Ice”

  1. I felt sad for the bears waiting in Churchill for enough ice to form 2002. They had starved for months. I wish they could move to Baffin or further east. Some of the news here is very good.

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