{"id":252219,"date":"2023-04-10T19:38:01","date_gmt":"2023-04-10T17:38:01","guid":{"rendered":"https:\/\/climatescience.press\/?p=252219"},"modified":"2023-04-10T19:38:04","modified_gmt":"2023-04-10T17:38:04","slug":"winter-sea-ice-habitat-for-polar-bears-still-abundant-enough-to-sustain-a-thriving-species","status":"publish","type":"post","link":"https:\/\/climatescience.press\/?p=252219","title":{"rendered":"Winter sea ice habitat for polar bears still abundant enough to sustain a thriving species"},"content":{"rendered":"\n
\"\"<\/figure>\n\n\n\n

<\/p>\n\n\n\n

From polarbearscience<\/a><\/p>\n\n\n\n

In contrast to summer sea ice, winter ice in the Arctic was again abundant this year. The slight decline since 1979 has so far been no cause for concern to polar bears,\u00a0who are thriving<\/a>.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

According to the US National Snow and Ice Data Center\u00a0report<\/a>\u00a0(5 April 2023), the average ice extent for March was 14.44 mkm2, considered the \u201cwinter\u201dvalue (as compared to \u201csummer\u201d which is the average for September). The extent for this year was certainly\u00a0below the long-term average<\/a>\u00a0but nowhere near being gone for good and nowhere near the low extent for winter at the height of the Eemain interglacial, when there was no ice\u00a0at all<\/em><\/strong>\u00a0in the Bering Sea (Polyak et al. 2010).<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

Numbers don\u2019t tell the whole story. Critically for polar bears, there was abundant ice in every subpopulation region where the species depends on newborn seals for food at this time of year, from the Bering Sea to the Barents Sea. There is even a fair amount off southeast Greenland, home to the\u00a0newest subpopulation of bears<\/a>.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

While some researchers and the media focus on the fact that some\u00a0Arctic ice is getting thinner<\/a>, this is not an issue for polar bears who require ice less than 2 m thick at this time of year (Derocher et al. 2004).<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

That means\u00a0abundant first year ice<\/a>, especially near shore and over Hudson Bay (shown below), is excellent news for polar bears.<\/p>\n\n\n\n

\"\"<\/figure>\n\n\n\n

In their 2004 paper, Derocher and colleagues state this unequivocally in the first sentence of their abstract:<\/p>\n\n\n\n

Polar bears (<\/em>Ursus maritimus) live throughout the ice-covered waters of the circumpolar Arctic, particularly in near shore annual ice over the continental shelf where biological productivity is highest.<\/em><\/p>\n\n\n\n

That means abundant first year ice<\/a>, especially near shore and over Hudson Bay, is excellent news for these species.<\/p>\n\n\n\n

Moreover, a study by George Durner and colleagues (2019:8625) on the use of sea ice in summer and winter by Southern Beaufort Sea polar bears over two recent decades (1996-2006 and 2007-2016) compared to a 1985-1995 decade baseline concluded:<\/p>\n\n\n\n

During the ice maximum season (i.e., winter), polar bears used the best habitat available, which changed relatively little across the three decades of study.<\/em><\/em><\/p>\n\n\n\n

Ian Stirling and colleagues (1999:294) could not have said it more clearly in their paper about Western Hudson Bay polar bears:<\/p>\n\n\n\n

Polar bears reach their lightest weights of the year in late March, just before the birth of the next cohort of ringed seal pups. This fact suggests it is the success of their hunting in spring and early summer that enables them to maximize the body reserves necessary for survival, reproduction, and nursing of cubs through the rest of the year.<\/em><\/p>\n\n\n\n

<\/p>\n\n\n\n

References<\/strong><\/p>\n\n\n\n

Derocher, A.E., Lunn, N.J., and Stirling, I. 2004. <\/strong>Polar bears in a warming climate. Integrative and Comparative Biology <\/em>44(2):163-176. https:\/\/doi.org\/10.1093\/icb\/44.2.163<\/a><\/p>\n\n\n\n

Durner, G.M., Douglas, D.C., and Atwood, T.C. 2019. <\/strong>Are polar bear habitat resource selection functions developed from 1985-1995 data still useful? Ecology and Evolution <\/em>9(15):8625-8638. https:\/\/doi.org\/10.1002\/ece3.5401<\/a><\/p>\n\n\n\n

Polyak, L., Alley, R.B., Andrews, J.T., et al. 2010.<\/strong> History of sea ice in the Arctic. Quaternary Science Reviews<\/em> 29:1757-1778. https:\/\/doi.org\/10.1016\/j.quascirev.2010.02.010<\/a><\/p>\n\n\n\n

Stirling, I., Lunn, N.J., and Iacozza, J. 1999.<\/strong> Long-term trends in the population ecology of polar bears in Western Hudson Bay in relation to climate change. Arctic <\/em>52(3):294-306. https:\/\/doi.org\/10.14430\/arctic935<\/a><\/p>\n\n\n\n

<\/p>\n\n\n\n

<\/p>\n","protected":false},"excerpt":{"rendered":"

According to the US National Snow and Ice Data Center\u00a0report\u00a0(5 April 2023), the average ice extent for March was 14.44 mkm2, considered the \u201cwinter\u201dvalue (as compared to \u201csummer\u201d which is the average for September).<\/p>\n","protected":false},"author":121246920,"featured_media":252230,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_coblocks_attr":"","_coblocks_dimensions":"","_coblocks_responsive_height":"","_coblocks_accordion_ie_support":"","_crdt_document":"","advanced_seo_description":"","jetpack_seo_html_title":"","jetpack_seo_noindex":false,"_jetpack_newsletter_access":"","_jetpack_dont_email_post_to_subs":false,"_jetpack_newsletter_tier_id":0,"_jetpack_memberships_contains_paywalled_content":false,"_jetpack_memberships_contains_paid_content":false,"footnotes":"","jetpack_publicize_message":"","jetpack_publicize_feature_enabled":true,"jetpack_social_post_already_shared":true,"jetpack_social_options":{"image_generator_settings":{"template":"highway","default_image_id":0,"font":"","enabled":false},"version":2},"jetpack_post_was_ever_published":false},"categories":[1],"tags":[691818252,691818250,691818251],"class_list":{"0":"post-252219","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","6":"hentry","7":"category-uncategorized","8":"tag-greenland","9":"tag-hudson-bay","10":"tag-polar-bears","12":"fallback-thumbnail"},"jetpack_publicize_connections":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/04\/0polar-bears-147.jpeg?fit=2048%2C1300&ssl=1","jetpack_likes_enabled":true,"jetpack_sharing_enabled":true,"jetpack_shortlink":"https:\/\/wp.me\/paxLW1-13C3","jetpack-related-posts":[{"id":316070,"url":"https:\/\/climatescience.press\/?p=316070","url_meta":{"origin":252219,"position":0},"title":"A good year for Svalbard polar bears due to abundant sea ice coverage","author":"uwe.roland.gross","date":"03\/04\/2024","format":false,"excerpt":"It remains to be seen how long the sea ice will hang around. However, these spring months are when polar bears gorge themselves on baby seals. As long as the bears can consume enough fat during this time, they are protected from the adverse effects of fasting over the summer\u2026","rel":"","context":"In \"Bear Island (Bj\u00f8rn\u00f8ya)\"","block_context":{"text":"Bear Island (Bj\u00f8rn\u00f8ya)","link":"https:\/\/climatescience.press\/?tag=bear-island-bjornoya"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/04\/00ar250.jpg?fit=1200%2C801&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/04\/00ar250.jpg?fit=1200%2C801&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/04\/00ar250.jpg?fit=1200%2C801&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/04\/00ar250.jpg?fit=1200%2C801&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/04\/00ar250.jpg?fit=1200%2C801&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":245927,"url":"https:\/\/climatescience.press\/?p=245927","url_meta":{"origin":252219,"position":1},"title":"Polar wildlife was thriving in 2022","author":"uwe.roland.gross","date":"27\/02\/2023","format":false,"excerpt":"A prominent Canadian zoologist says that Arctic and Antarctic wildlife continued to thrive in 2022 despite predictions of impending catastrophe.","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/0mail-1.png?fit=1200%2C623&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/0mail-1.png?fit=1200%2C623&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/0mail-1.png?fit=1200%2C623&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/0mail-1.png?fit=1200%2C623&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/0mail-1.png?fit=1200%2C623&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":334659,"url":"https:\/\/climatescience.press\/?p=334659","url_meta":{"origin":252219,"position":2},"title":"Arctic sea ice at the summer solstice: more polar bear habitat than 2022 after hottest year on record","author":"uwe.roland.gross","date":"26\/06\/2024","format":false,"excerpt":"We are just into the 2024 sea ice melt season in the Arctic with no signs of any big, dramatic changes despite claims that 2023 was the warmest year on record (since 1850). There is still abundant sea ice habitat for polar bears ahead of the summer months (July-September) when\u2026","rel":"","context":"In \"Arctic sea ice\"","block_context":{"text":"Arctic sea ice","link":"https:\/\/climatescience.press\/?tag=arctic-sea-ice"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0wild-polar-bear-mother-and-cub-on-the-pack-ice-picture-id1181703271.jpg?fit=1200%2C717&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0wild-polar-bear-mother-and-cub-on-the-pack-ice-picture-id1181703271.jpg?fit=1200%2C717&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0wild-polar-bear-mother-and-cub-on-the-pack-ice-picture-id1181703271.jpg?fit=1200%2C717&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0wild-polar-bear-mother-and-cub-on-the-pack-ice-picture-id1181703271.jpg?fit=1200%2C717&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0wild-polar-bear-mother-and-cub-on-the-pack-ice-picture-id1181703271.jpg?fit=1200%2C717&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":245937,"url":"https:\/\/climatescience.press\/?p=245937","url_meta":{"origin":252219,"position":3},"title":"Polar Wildlife Report reveals Arctic and Antarctic animals were thriving in 2022","author":"uwe.roland.gross","date":"27\/02\/2023","format":false,"excerpt":"Crockford concludes: \u201cIn both the Arctic and Antarctic, less summer sea ice has meant increased primary productivity, which in turn has meant more food for all animals. This explains in part why polar wildlife continues to thrive, even in areas with much reduced summer sea-ice coverage.\u201d","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/image-903.png?fit=1200%2C750&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/image-903.png?fit=1200%2C750&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/image-903.png?fit=1200%2C750&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/image-903.png?fit=1200%2C750&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2023\/02\/image-903.png?fit=1200%2C750&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":331666,"url":"https:\/\/climatescience.press\/?p=331666","url_meta":{"origin":252219,"position":4},"title":"New data show Svalbard polar bears are fatter than they were in 1993 despite continued low sea ice","author":"uwe.roland.gross","date":"05\/06\/2024","format":false,"excerpt":"Researchers at the Norwegian Polar Institute have finally updated their spring data, which show male polar bears in 2024 were even fatter than they were in 1993 and litter sizes of new cubs were just as high, despite continued low sea ice in the region over the summer months especially.","rel":"","context":"In \"Norwegian Polar Institute\"","block_context":{"text":"Norwegian Polar Institute","link":"https:\/\/climatescience.press\/?tag=norwegian-polar-institute"},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0ar250.jpg?fit=1200%2C801&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0ar250.jpg?fit=1200%2C801&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0ar250.jpg?fit=1200%2C801&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0ar250.jpg?fit=1200%2C801&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2024\/06\/0ar250.jpg?fit=1200%2C801&ssl=1&resize=1050%2C600 3x"},"classes":[]},{"id":206010,"url":"https:\/\/climatescience.press\/?p=206010","url_meta":{"origin":252219,"position":5},"title":"Svalbard polar bear data for spring 2022, low June ice unlikely to affect health or survival","author":"uwe.roland.gross","date":"27\/06\/2022","format":false,"excerpt":"Sea ice around Svalbard, Norway has receded dramatically over the last few weeks and is now at levels similar to 2018 and 2006. But the data are in for the 2022 spring season and they show the bears are still thriving. While polar bear specialists insist that summer sea ice\u2026","rel":"","context":"Similar post","block_context":{"text":"Similar post","link":""},"img":{"alt_text":"","src":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0two-svalbard-bears_web_shutterstock_578908810.jpg?fit=1200%2C800&ssl=1&resize=350%2C200","width":350,"height":200,"srcset":"https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0two-svalbard-bears_web_shutterstock_578908810.jpg?fit=1200%2C800&ssl=1&resize=350%2C200 1x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0two-svalbard-bears_web_shutterstock_578908810.jpg?fit=1200%2C800&ssl=1&resize=525%2C300 1.5x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0two-svalbard-bears_web_shutterstock_578908810.jpg?fit=1200%2C800&ssl=1&resize=700%2C400 2x, https:\/\/i0.wp.com\/climatescience.press\/wp-content\/uploads\/2022\/06\/0two-svalbard-bears_web_shutterstock_578908810.jpg?fit=1200%2C800&ssl=1&resize=1050%2C600 3x"},"classes":[]}],"_links":{"self":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/252219","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/users\/121246920"}],"replies":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=252219"}],"version-history":[{"count":7,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/252219\/revisions"}],"predecessor-version":[{"id":252232,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/posts\/252219\/revisions\/252232"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=\/wp\/v2\/media\/252230"}],"wp:attachment":[{"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=252219"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=252219"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/climatescience.press\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=252219"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}