By Paul Homewood

Last December, researchers vigorously promoted a possible 27% decline in Western Hudson Bay (WH) polar bear abundance but kept hidden the fact that adjacent Southern Hudson Bay (SH) numbers increased by 30% over the same period.

And surprise, surprise: the bombshell SH results call into question everything the ‘experts’ have been saying about polar bears in Hudson Bay for years.

I finally got a copy of the 2021 WH survey report from the Nunavut government, which was reported on by the media around the world in December 2022. The Nunavut government also sent along a copy of the 2021 SH report (helpfully asking, “would you also like the SH report?”), published at virtually the same time. The existence of a SH report was never mentioned by any of the media articles in December, even though it was referenced several times in the WH report, which suggests reporters never actually saw the WH report but were simply given a press release with approved talking points.

The WH 2011 population estimate was 949 (range 618-1280), the 2016 estimate was 842 (range 562-1121), and 2021 estimate was 618 (range 385-852). The media must have been given the 27% figure representing the drop between 2016 and 2021 in a press release, because that figure isn’t mentioned in the WH report.

According to Andrew Derocher, of the University of Alberta, regarding the WH population, “The actual decline is a lot larger than I would have expected.” [CBC News, 23 December 2022]

I’ll say. However, the apparent decline from 2016 to 2021 was not statistically significant and neither was the decline between 2011 and 2021: the authors state this explicitly on pg. 29 of the WH report.

Oddly, that’s not the impression the press seems to have been given considering phrases used in their headlines, such as “population plummets,” “polar bears vanishing,” “polar bears…in sharp decline,” and “polar bears disappearing fast.”

The WH report authors state that abundance of adult male bears remained unchanged over the three sampling periods but that a decline in abundance of adult females and subadult bears (especially in the area around Churchill) seems to have driven an apparent decline in overall numbers. A suggestion was made that perhaps some Churchill-area females and subadults had simply relocated a bit north or south but the authors shot that notion down.

Although, the estimated abundance of adult female and subadult bears in Area 2 [i.e. around Churchill] decreased significantly between the 2011 and 2021 surveys, concurrent increases of these types of bears in Areas 1 (Cape Tatnum) [to the south] or 3 (Nunavut) [to the north] of WH were not found (Table 13). [WH report, Atkinson et al. 2022, pg. 32]

So, the missing females and subadults didn’t move a bit north or south, but did they perhaps move further south, into Southern Hudson Bay?

Notably, between 2016 and 2021, the estimated abundance of SH increased by 223 bears while that of WH decreased by 224 (Northrup et al. 2022). Changes in both subpopulations, at least between 2016 and 2021, could therefore be accounted for by movement of WH bears into SH.

Full story here.

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October 19, 2023 at 07:33AM