Polar bear habitat over Hudson Bay was average this week (at 60% coverage), despite the odd pattern of breakup – but the end of spring in the Arctic is only 5 days away and there is still plenty of polar bear habitat in all regions.
According to the Canadian Ice Service (CIS), there is still more ice in the eastern portion of the bay than usual and much less in the northwest (Fig. 1 below). There is far more ice than average ice in Hudson Strait, the approach to southern Davis Strait.
Andrew Derocher reports (Fig. 3, via twitter) that 7 out of 9 Western Hudson Bay females with collars are still out on the ice (see previous post: Up to 20% of collared polar bears found on ice that officially does not exist, says the PBSG). Notice in his map that at least 3 of those bears appear to be in open water. It’s likely the ice-melt phenomenon I’ve discussed before, that satellites interpret melt-ponds on ice as open water. This suggests, as far as polar bears are concerned, that there is actually more “useable” sea ice out there than the ice maps indicate.
A few bears have come ashore (a few always do before it’s absolutely necessary), but at least one of those captured on camera was in excellent condition (see video here).
See discussion of breakup dates here, here, and here – but it is clear we are well past the point of breakup being “early” (for dates since 1991) for Western Hudson Bay polar bears, and approaching average (1 July).
In the Beaufort Sea, ice coverage is a bit below average (Fig. 4) but there is still lots of ice left for bears to keep hunting (Figs. 5), with much 40-50% concentration of ice showing.
The same is true for Barents Sea bears (Fig. 7) – somewhat less ice than average but still enough to serve as a hunting platform, according to the Norwegian Ice Service (NIS). And despite what some folks will tell you, apparently that’s good enough – Svalbard bears are doing very well this year, with a good crop of new cubs.
What about the entire Arctic? A bit less sea ice than average globally (Fig. 8) but still enough over continental shelves for polar bears who will eventually have to spend their summer fast on shore, to continue hunting seals a bit longer.