Susan Crockford
It’s been an early breakup year for Hudson Bay, but the rate of sea ice loss isn’t accelerating. While some bears in West Hudson Bay have been on land for weeks, others are still melting remnants of sea ice, much of which cannot be seen by satellite. This is only the third year since 2014 that the bay has had less-than-normal ice, meaning most years since then have had normal or near-normal ice cover, similar to the 1980s. like no The disaster is getting worse about the media-reported sea ice loss story of the West Hudson Bay polar bear.
From Follow the map on, of the 38 tags or necklaces visible on the bears as of 11 July 2023, 16 bears (42%) were on land and 22 (58%) were still at sea. That is almost identical to 40/60 percent split last week when there’s even more ice.
This week’s ice cover
For the week of July 10, 2023, this tape chart from the Canadian Ice Service (below) shows that at least four bears tagged (see chart above) is lying on ice that the satellites cannot see. Not sure if they’re swimming because they’re inside same place last week. This is an earlier-than-usual breakup pattern, similar to what was recorded in the two decades following the financial crisis. step change in 1995.
polar bears and sea ice
NASA Earth Observatory recently (July 12, 2023) provided the opportunity for polar bear activists to promote their terrifying story about polar bears in Hudson Bay (my cheeky):
In 2023, some West Hudson Bay polar bear begin to return to the inner shore mid-June, but others lingered on the ice until July. The University of Alberta scientist said: “Mid-June is an early time to have bears on land. Andrew Derocher. “When I started studying polar bears in West Hudson Bay in the 1980s, we would have bears on the ice in August.”
…
Although some bears swam to shore early, Derocher note that many bears were still out on the ice in early July, despite how little ice was left and how fragmented the ice eventually became.
“The bears on the ice are hanging at an extremely low level of ice,” Derocher said. “But they would rather be there trying to kill another seal than being on land with little or nothing to eat. Bears can feed and continue to gain weight in the summer if they have rocks. For polar bears, it’s really survival of the fattest.”
Funny that Derocher doesn’t mention that polar bears are premieres on tape in August in both 2020 and 2022: no, he dropped that part and emphasized that the breakup was at the beginning of this year.
Do polar bears in Hudson Bay kill seals in July and August
In addition, despite Derocher’s statements to NASA, there is no documentary evidence that polar bears west or south of Hudson Bay regularly kill seals due to sea ice melt in July and August. Derocher assumption they do but he has no proof that this actually happens because no one has ever studied the phenomenon. It is unlikely that more than a few seals will spend extended periods of time on sea ice in midsummer as most of them, including adults and young, will be out feeding in open water.
What is the normal farewell for Hudson Bay?
The chart below is from a paper by Ian Stirling and colleagues (2004), and it shows what the normal or normal sea ice melt pattern was like from 1971 to 2000. today is the same as expected in late or about two july a few weeks earlier (dark grey). According to an analysis by Castro de la Guardia and colleagues (2017), the breakup in 2015 was about two weeks earlier than before 1995 or similar to this year.
Ice layer mid-July 2015-2023
However, this year’s pattern is unusual compared to nine years ago. As of 2014, only 3 of the 9 years (2023, 2021 and 2017) had less ice than usual in mid-July. Four years (2016, 2019, 2020 and 2022) produce conditions that are considered “normal” based on long-term data by Stirling et al (1971-2000), while 2015 and 2018 have a lot of ice. mid-July but more than usual in the northeast quadrant.
In other words, Hudson Bay experienced normal ice cover in mid-July more often than reduced ice cover. This means loss of sea ice in the Gulf not accelerated yetinstead of ice covered was overall improvement since 2014 compared to two decades ago. That’s why announced a 27% decrease in polar bear populations for the West Hudson Bay from 2017 to 2021 cannot be blamed for a lack of sea ice: sea ice conditions were mostly very good in those years.
Check out the tape charts below, starting this year:
Presenter
Castro de la Guardia, L.., Myers, PG, Derocher, AE, et al. 2017. The sea ice cycle west of Hudson Bay, Canada, from a polar bear’s perspective. Flow of marine ecology 564: 225–233. http://www.int-res.com/abstracts/meps/v564/p225-233/
Stirling, I., Lunn, NJ, Iacozza, J. et al. 2004. Distribution and abundance of polar bears on the southwest coast of Hudson Bay during the open water season, in relation to population trends and annual ice patterns. North Pole 57(1):15-26. https://journalhosting.ucalgary.ca/index.php/arctic/article/view/63539 Open access.
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