Expert admits polar bears in Svalbard are thriving despite the greatest loss of sea ice in the Arctic

In an article published last week, polar bear specialist Jon Aars is quoted as saying that Svalbard bears are “unexpectedly” thriving. However, he fails short of admitting that the bears don’t really need summer ice as long as they are well-fed in spring, which they have been for the last two decadesthis year included.

Aars said the sea ice in this area is declining more than twice as fast as anywhere else in the Arctic. But the polar bears here — unexpectedly — are thriving. [E. Haavik, Svalbard’s polar bears persist as sea ice melts — but not forever, 21 July 2022; my bold]

Spring 2018, Barents Sea

The suggestion by Aars that the Svalbard archipelago could one day be ice-free for the entire year is speculative hyperbole but even if that were to happen, it would only mean the permanent movement of 300 or so Svalbard bears to Franz Josef Land (still within the Barents Sea) where ice conditions are less volatile.

This year is typical of most recent years in summer: Svalbard is devoid of ice but there is still plenty around Franz Josef Land to the east and to the north, where the Arctic pack ice begins (see ice chart below for 20 July 2022).

For the last ten years or so, we have been getting some news ‘feature’ article, press release, or tweet over the summer full of hand-wringing comments from polar bear specialists about the dismal future of Svalbard bears. Yet, every year current research has revealed the bears are still thriving.

In the last two decades, ice has often not returned early enough in the fall for females bears to use the islands on the east coast of the archipelago for denning (e.g. 2020, see chart below). We know that in these cases, females with make their dens on the sea ice or on Franz Josef Land.

However, every year the ice has certainly come by late winter and early spring, in time for the critical polar bear feeding season, when newborn seal pups are available in the landfast ice as well as in the pack ice (see 2021 February and March charts below). Some females that have had their pups further east travel to the eastern Svalbard region for spring feeding, which seems to have been a net benefit, since a 2020 study found females in 2017 were in better condition than they had been in 2004 (Lippold et al. 2020):

Here is the critical take-home message about polar bears in this region:

“Despite the declining sea ice in the Barents Sea, polar bears are likely not lacking food as long as sea ice is present during their peak feeding period.” [Lippold et al. 2020:988]

Franz Josef Land in winter

Even in 2012, when there was little ice around eastern Svalbard at the end of January, Franz Josef Land was surrounded by ice:

The same was true in 2020 at the end of December:

Franz Josef Land polar bear 2019.

References

Lippold, A., Bourgeon, S., Aars, J., Andersen, M., Polder, A., Lyche, J.L., Bytingsvik, J., Jenssen, B.M., Derocher, A.E., Welker, J.M. and Routti, H. 2019. Temporal trends of persistent organic pollutants in Barents Sea polar bears (Ursus maritimus) in relation to changes in feeding habits and body condition. Environmental Science and Technology 53(2):984-995.

via polarbearscience

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July 27, 2022 at 12:10AM

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