There has been abundant sea ice in the Chukchi Sea this summer: so much so that walrus herds have not found it necessary to use beaches on the Alaskan coast as resting haulouts. Now, in early September, almost the entire northern Chukotka coast is covered in ice, blocking use of those beaches that have been traditionally used in September through November. Wrangel Island (an important denning area for polar bears) is still almost surrounded by ice, which hasn’t happened in decades.
Just two years ago, a big deal was made of the fact that the entire coast of Alaska was ice-free by early August and that walrus herds had come ashore at Point Lay earlier than any year since 2007 – all put down to climate change. Last year, walrus started to come ashore one day earlier than in 2019, on July 29. Although no one has presented any evidence that the walrus are suffering in any way due to using beach haulouts during the ice-free season (MacCracken et al. 2017), the haulouts are still presented as bad news and portends of catastrophe to come.
This year is a totally different story and of course, the biologists are suddenly silent.
Sea ice in the Chukchi Sea this year at 29 July 2021 (below) shows Point Lay was ice-free (as it has been for many years), but we have heard nothing about walrus haulouts as we did in years past.
At 31 August 2021 (below) there was not much less ice in the Chukchi Sea and still no sign of walrus at land haulouts in Alaska (Fischbach et al. 2016). Wrangel Island is still almost surrounded by ice and ice covered much of the Chukotka coast on the mainland, including the famous cliff haulout at Cape Schmidt that is the focus of my upcoming book on the deception in David Attenborough’s Our Planet documentary:
In 2019, there was virtually no ice left in the Chukchi Sea at the end of August:
You can see the shallow area of the Chukchi (pale blue) in the chart below for 2 September 2021, where walrus prefer to feed: this year the ice is much closer to these shallow regions and the strip of ice along the Chukotka coast shows clearly.
The last time there was ice surrounding Wrangel Island in early September was 2003 but it was only a patch:
It wasn’t until 2001 that so much Chukchi Sea ice was routine at the end of August:
Just for comparison, below is the same chart for 2021 from NSIDC:
References
Fischbach, A.S., Kochnev, A.A., Garlich-Miller, J.L. and Jay, C.V. 2016. Pacific walrus coastal haulout database, 1852-2016 – Background Report. USGS Open-File Report 2016-1108. DOI: 10.3133/ofr20161108 PDF HERE, download here.
MacCracken, J.G., Beatty, W.S., Garlich-Miller, J.L., Kissling, M.L and Snyder, J.A. 2017. Final Species Status Assessment for the Pacific Walrus (Odobenus rosmarus divergens), May 2017 (Version 1.0). US Fish & Wildlife Service, Anchorage, AK. Pdf here (8.6 mb).
via polarbearscience
September 3, 2021
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