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From Polar Bear Science
Dr. Susan Crockford
The 234 or so polar bears inhabiting the SE tip of Greenland, mentioned to be genetically and ecologically distinctive as a result of they’re “surviving with out ice“, have been experiencing sea ice formation alongside the shoreline this month identical to different bears throughout the Arctic. Recall that shorefast ice formation attracts seals within the fall, which polar bears hunt efficiently, and the next spring (April/Might) present a platform for ringed seals to offer beginning to their pups, which polar bears eat with homosexual abandon.
The picture above was taken by Kristin Laidre in March 2016: a bear this fats on the finish of winter (i.e. earlier than ringed seals are born within the spring) resides in productive habitat.
In accordance with the paper, the land-bound quick ice that almost all ringed seals use to offer beginning and nurse their pups in spring (April-Might) remains to be routinely obtainable in SE Greenland (Laidre et al. 2022; McLaren 1958; Stirling and Oritsland 1995).
Here’s what polar bear biologist Steve Amstrup (2003:592) has to say concerning the spring feeding:
“In some areas, predation on pups is intensive. Hammill and Smith (1991) estimated that polar bears yearly kill as much as 44% of latest born seal pups if circumstances are proper.”
If this ice lasts solely till Might 2023, it will be 180 days of productive sea ice and a far cry from the legendary ‘100 days’ which fashions recommend is the brink for polar bear demise (Molnár et al. 2010, 2020). That is apparently why polar bears on this area are doing simply in addition to these dwelling in NE Greenland: in different phrases, thriving regardless of the pessimistic prophesies of consultants.
Chart under is for 17 December 2022 (MASIE):
The map under exhibits 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 College Press, Baltimore.
Laidre, Ok.L., Supple, M.A., Born, E.W., et al. 2022. Glacial ice helps a definite and undocumented polar bear subpopulation persisting in late twenty first century sea-ice circumstances. 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) within the Jap Canadian Arctic. Fisheries Analysis Board of Canada, Ottawa. Bulletin 118. Pdf right here.
Molnár, P.Ok., Bitz, C.M., Holland, M.M., Kay, J.E., Penk, S.R. and Amstrup, S.C. 2020. Fasting season size units temporal limits for world polar bear persistence. Nature Local weather Change 10:732-738. https://doi.org/10.1038/s41558-020-0818-9
Molnár, P.Ok., Derocher, A.E., Theimann, G., and Lewis, M.A. 2010. Predicting survival, copy and abundance of polar bears underneath local weather change. Organic Conservation 143:1612-1622. http://www.math.ualberta.ca/~mlewis/Publicationspercent202010/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 within 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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