Earth Day sea ice habitat during critical spring season for Arctic seals, polar bears, and walrus

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From polarbearscience

This is the most important time of year for Arctic marine mammals that spend time above the ice: birthing, breeding, and feeding. And there is plenty of the right kind of ice available for those activities this year, as there was two years ago at the same time.

Arctic overall

NSIDC MASIE chart for 21 April 2023

Sea ice thickness

Amazing band of 3-5m thick ice in Foxe Basin (north of Hudson Bay), and along the entire east coast of Greenland and the Russian Far East. This doesn’t show up on other charts as significant because its very thick first year ice rather than the thick multi-year ice seen in the Arctic Basin north of Greenland and Ellesmere Island.

In the Chukchi Sea, this thick ice charts as ‘thick first year’ ice (dark green). Areas of purple in the Bering Sea are thinner ice that are critical feeding habitat at this time of year for Pacific walrus, especially pregnant females that will give birth next month. Walrus need areas of easily-broken thin ice or open water so that they can enter the water to feed, as do bearded seals.

Barents Sea

Courtesy Norwegian Ice Service. Note the abundance of ice along the coast of Greenland and between the Svalbard archipelago (at centre) and Franz Josef Land to the east.

Sea ice around the Svalbard archipelago in the middle of the Barents Sea ice has been above the long-term average for weeks now, as the graph below shows. This is great news for polar bears and seals because this is when they need sea ice the most.


Polar bears on Hudson Bay

Female bears with satellite collars (blue and orange) or males or juveniles with ear tags (purple) can be seen well on the ice of Hudson Bay, along with females that gave birth earlier in the year with their 4 month old cubs. Chart below courtesy Andrew Derocher. Blue icons are Western Hudson Bay females and the orange are Southern Hudson Bay females.

Note that the dark green in the chart below is thick first year ice, over 1m thick.