Polar Bears of SE Greenland Get Shorefast Ice Necessary to Hunt Seals: Not So Unique After All

From Polar Bear Science

Dr. Susan Crockford

The 234 or so polar bears inhabiting the SE tip of Greenland, said to be genetically and ecologically unique because they are “surviving without ice“, have been experiencing sea ice formation along the shoreline this month just like other bears across the Arctic. Recall that shorefast ice formation attracts seals in the fall, which polar bears hunt successfully, and the following spring (April/May) provide a platform for ringed seals to give birth to their pups, which polar bears eat with gay abandon.

The photo above was taken by Kristin Laidre in March 2016: a bear this fat at the end of winter (i.e. before ringed seals are born in the spring) is living in productive habitat.

According to the paper, the land-bound fast ice that most ringed seals use to give birth and nurse their pups in spring (April-May) is still routinely available in SE Greenland (Laidre et al. 2022; McLaren 1958; Stirling and Oritsland 1995).

Here is what polar bear biologist Steve Amstrup (2003:592) has to say about the spring feeding:

In some areas, predation on pups is extensive. Hammill and Smith (1991) estimated that polar bears annually kill up to 44% of new born seal pups if conditions are right.

If this ice lasts only until May 2023, it would be 180 days of productive sea ice and a far cry from the mythical ‘100 days’ which models suggest is the threshold for polar bear demise (Molnár et al. 2010, 2020). This is apparently why polar bears in this region are doing just as well as those living in NE Greenland: in other words, thriving despite the pessimistic prophesies of experts.

Chart below is for 17 December 2022 (MASIE):

The map below shows the boundary of the proposed ‘SE Greenland’ polar bear subpopulation from the paper by Kristen Laidre and colleagues (2022):

References

Amstrup, S.C. 2003. Polar bear (Ursus maritimus). In Wild Mammals of North America, G.A. Feldhamer, B.C. Thompson and J.A. Chapman (eds), pg. 587-610. Johns Hopkins University Press, Baltimore.

Laidre, K.L., Supple, M.A., Born, E.W., et al. 2022. Glacial ice supports a distinct and undocumented polar bear subpopulation persisting in late 21st century sea-ice conditions. Science 376 (6599): 1333-1338. https://www.science.org/doi/10.1126/science.abq5267

McLaren, I.A. 1958. The biology of the ringed seal (Phoca hispida Schreber) in the Eastern Canadian Arctic. Fisheries Research Board of Canada, Ottawa. Bulletin 118. Pdf here.

Molnár, P.K., Bitz, C.M., Holland, M.M., Kay, J.E., Penk, S.R. and Amstrup, S.C. 2020. Fasting season length sets temporal limits for global polar bear persistence. Nature Climate Change 10:732-738.  https://doi.org/10.1038/s41558-020-0818-9

Molnár, P.K., Derocher, A.E., Theimann, G., and Lewis, M.A. 2010. Predicting survival, reproduction and abundance of polar bears under climate change. Biological Conservation 143:1612-1622. http://www.math.ualberta.ca/~mlewis/Publications%202010/Molnar-Derocher-Thiemann-Lewis.pdf

Stirling, I. and Øritsland, N. A. 1995. Relationships between estimates of ringed seal (Phoca hispida) and polar bear (Ursus maritimus) populations in the Canadian Arctic. Canadian Journal of Fisheries and Aquatic Sciences 52: 2594 – 2612. http://www.nrcresearchpress.com/doi/abs/10.1139/f95-849#.VNep0y5v_gU

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Tom Halla
December 20, 2022 6:21 pm

Bad bears! Not fitting the models!

Bryan A
Reply to  Tom Halla
December 20, 2022 8:42 pm

Bad News Bears…Breaking the Narrative

John Hultquist
December 20, 2022 6:57 pm

 Cardiologists should be studying fat bears and the gain-loss of weight over just a few months’ time. The physiology of these rapid changes might help about half the USA’s people population.  

Duker
Reply to  John Hultquist
December 20, 2022 8:25 pm

Im not sure of this but I think its related to the reasons pacific islanders get so obese. They stored up body fat in good times as they may have needed in the hard times. Modern era away from the islands means for many the good times roll on continuously

Redge
Reply to  Duker
December 20, 2022 11:15 pm

We all store up body fat for hard times, it’s how we survived in days gone by. That’s why some fat tastes good

The issue with obesity is we are genetically programmed to store fat and in affluent counties, there is way too much in our diets

Last edited 1 month ago by Redge
Bill Powers
Reply to  Redge
December 21, 2022 6:42 am

Not to mention a severe lack of exercise. Affluence is a double edged sword but give me affluence over the alternative.

BCBill
Reply to  John Hultquist
December 20, 2022 8:43 pm

Back in the day when Greenpeace wasn’t an evil corporation bent on world domination, a friend of mine was lying on the beach with his layer of Canadian winter blubber when Greenpeacers painted him with green paint to make his pelt unmarketable. Well, it could have happened.

abolition man
Reply to  John Hultquist
December 20, 2022 10:55 pm

Bear and primate metabolic processes are quite different. If a human, even a Pacific Islander like a Maori, ate a high fat, high protein diet like the polar bear’s they would go into ketogenesis and get leaner, not fatter! Think of a linebacker as opposed to a lineman. A polar bear would probably suffer ill health by eating the high carb/processed food diet of the obese!

Scarecrow Repair
December 20, 2022 9:37 pm

I have a semi-off-topic question about polar bears and seals. Cattle turn grass into meat for wolves; seals turn fish into meat for polar bears. Now wolves can’t eat grass, but grizzlies can sure eat fish, and I assume the same for polar bears.

It seems inefficient for polar bears to eat seals when they could just eat fish instead. I realize there is no central planner studying efficient energy paths for optimal ecological niches, but there must be some practical reason why polar bears prefer seals rather than fish, and I can only imagine fish don’t get as big as baby seals, can evade polar bears easier than seals, mostly live too deep for polar bears to dive, and there are few rivers in polar bear country suitable for fish.

Does anyone know anything definitive about this?

Redge
Reply to  Scarecrow Repair
December 20, 2022 11:18 pm

Polar bears don’t have the dexterity to make fishing rods

Bill Powers
Reply to  Redge
December 21, 2022 6:47 am

Plus they have a helluva time worming their hooks. Until they can learn how to make artificial lures, seals make a great alternative.

Rod Evans
Reply to  Scarecrow Repair
December 21, 2022 1:25 am

Have you ever tried to catch a fish without a net or a day spent on the river bank thinking about life?
It is easier to catch concentrated fish in the form of seals I think..

rah
December 20, 2022 10:06 pm

100 Times Faster | Real Climate Science

“Greenland’s Glaciers Might Be Melting 100 Times As Fast As Previously Thought
A computer model has been created by researchers at the Oden Institute for Computational Engineering and Sciences at The University of Texas at Austin that determines the rate at which Greenland’s glacier fronts are melting.”

And I MIGHT hit the Powerball Grand Prize tomorrow! My odds are at least a good as their computer model is for being accurate. And I haven’t even bought a Powerball ticket!

John Hultquist
Reply to  rah
December 21, 2022 9:43 am

Austin researchers ought to be studying the de-peopling of the Americas south of the Texas border. This year the flow amounts to (roughly) 450,000,000 pounds [maybe less because of the large number of small ones]. A swath of territory from the Gulf to the Pacific could be depressed and a new sea route established.
That could put some truckers out of business. 😁

Rod Evans
December 21, 2022 1:12 am

If Polar Bears are able to survive and grow their population in South East Greenland, then there is little to worry about, from a Polar Bear survival viewpoint.
The South East of Greenland must be the mildest least arctic like home for a Polar Bear to choose.

antigtiff
December 21, 2022 7:12 am

Reporters in helicopters report seeing a bloody mess below…the bears are munching down those baby seals.

Brad-DXT
December 21, 2022 8:08 am

This population of polar bears adapts to it’s environment.
Its like they have some sort of intelligence that is lacking in leftists and their talking heads.

Pat from Kerbob
December 22, 2022 12:21 am

I miss Griff
I haven’t read anything really stupid in a while

Ireneusz Palmowski
December 23, 2022 3:39 am

Powerful stratospheric intrusion reaches southern US.
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