Moreover, considering that 2021 fall ice formation for the Arctic in general is well ahead of 2016 (and every year since, except 2018), it’s hard to see why human-caused global warming caused by ever-increasing CO2 emissions explains the slow freeze-up of Hudson Bay. Timing of Hudson Bay freeze-up has always been highly variable from one year to the next (Castro de la Guardia et al. 2017: Fig. 3, copied below). The average freeze-up date in the 1980s was 16 November ± 5 days, while from 2005-2015 this had shifted about a week to 24 November ± 8 days (Castro de la Guardia et al. 2017:230). This year freeze-up was later than usual but last year and the three years before that the ice froze as early as it did in the 1980s. Cue the zombie apocalypse.
UPDATE 11 December 2021: see chart below from Andrew Derocher on the position of tagged WH bears at 10 December.
Posted onOctober 15, 2021|Comments Off on No signs of a climate emergency for W. Hudson Bay polar bears this year ahead of UN climate meeting
I’ve been told that another complete aerial survey of the Western Hudson Bay polar bear subpopulation (from the Nunavut to Ontario boundaries) was conducted in August this year and that the bears have been hanging out further south than usual. It will be years before the results of the population count are published, of course (especially if it’s good news) but my contacts also say virtually all of the bears are in great condition again this year.
Posted onJuly 22, 2021|Comments Off on Western Hudson Bay polar bears: still some out on the sea ice, some causing trouble
As of Monday (19 July), more polar bears had come ashore near Churchill and on the shores of Wakusp National Park but some are still out on the bay. The pattern of ice breakup this year means most bears will come ashore well south of Churchill and make their way north over the summer and fall. There have been two Churchill ‘problem’ bear reports so far but not one for this week, so I’ll go ahead and post without it.
Posted onJune 23, 2021|Comments Off on Polar bears of western Hudson Bay still on the ice at third week June
According to the tracker map provided by Andrew Derocher (University of Alberta), all of the western Hudson Bay polar bear females that still have operational satellite collars (deployed in 2019) are still out on the ice of Hudson Bay. The Explore.org live video cam that sits on the shore of Wapusk National Park just south of Churchill has been capturing images of caribou and birds but so far, no polar bears. Last year, the first bear seen onshore by the cameras (shown in the video) was on 13 July.
It wasn’t until a month later that more bears were seen: the fat mother and cub in the screencap below were spotted on 18 July 2020 and the last of the collared bears didn’t come ashore until late August:
This year at 21 June, only 6 collars still operating but only one of them is anywhere close to shore yet (courtesy Andrew Derocher via twitter, below):
That ice in the middle of the bay is still primarily very thick first year ice, as the chart for this third week of June shows (below):
Posted onJune 17, 2021|Comments Off on Polar bear habitat update and the progress of breakup on Hudson Bay
At mid-month, there is still an abundance of thick first year ice over much of Hudson Bay, suggesting that – yet again – this will not be an early breakup year for Western Hudson Bay polar bears. The early breakup years in the past (like 2010) that generated all kinds of panic amongst polar bear specialists have not developed into ever-continuing declining trend (Lunn et al. 2016) or another abrupt step-change like there was in 1998/99 (Castro de la Guardia et al. 2017).
Posted onJune 8, 2021|Comments Off on Polar bear habitat in Canada at the first week of June sees widening of critical polynyas
Winds primarily cause the apparent sea ice ‘breakup’ in late spring through the widening of persistent polynyas and shore leads. This year the development of critical open water areas in Canada (which are important feeding areas for polar bears) is on track with previous years in most areas, although there is a lot of year-to-year variability.
Posted onNovember 3, 2020|Comments Off on Western & Southern Hudson Bay polar bears experience earliest freeze-up in decades
This is shaping up to be one of the shortest ice-free seasons in at least 20 years for both Western and Southern Hudson Bay polar bears.
Hudson Bay sea ice at 2 November 2020. NSIDC Masie chart.
Last week, sea ice started forming along the shore of Hudson Bay, from the north end all the way south into James Bay. So far, the shorefast ice that’s forming is only a narrow strip along the coast but is thickening and becoming broader each day, which means that unless something changes dramatically, the bears should all be on the ice at the end of the week, an exodus from shore that hasn’t happened this early in WH since 1993 (the earliest since 1979).
The last WH tagged polar bear didn’t leave the ice this year until 21 August, which means if it’s on the ice by the end of this week it will have spent only 11 weeks onshore – less than 3 months. Even the first bears that came ashore in mid-July will have only spent about 16 weeks on land – at least a month less than they did a decade ago (Stirling and Derocher 2012). Four months spent ashore was the historical average for Western Hudson Bay bears in the 1970s and 1980s (Stirling et al. 1977, 1999). This year, most polar bears will have spent only about 13-14 weeks on land because they did not come ashore until early August.
Posted onOctober 23, 2020|Comments Off on Polar bear research on hold in Western Hudson Bay due to COVID-19 restrictions
After spring polar bear research was cancelled in Western Hudson Bay (and pretty much everywhere else) this year because of Covid 19 concerns, it now transpires that fall research is out as well. Travel restrictions implemented by government departments and university administrations (not the health department) apparently mean fall programs to assess the health and status of polar bears in Western Hudson Bay have been put on hold.
Triplet litter of polar bear cubs spotted in Wakusp National Park, Western Hudson Bay. 23 October 2020. Courtesy Explore.org.
Posted onSeptember 20, 2020|Comments Off on Potential impact of the second-lowest sea ice minimum since 1979 on polar bear survival
The annual summer sea ice minimum in the Arctic has been reached and while the precise extent has not yet been officially determined, it’s clear this will be the ‘second lowest’ minimum (after 2012) since 1979. However, as there is no evidence that polar bears were harmed by the 2012 ‘lowest’ summer sea ice this year’s ‘second-lowest’ is unlikely to have any negative effect.
In this summary of how polar bears have been doing since the the lowest sea ice minimum in 2012, I show that contrary to all predictions, polar bears have been thriving despite reduced summer ice in the Barents, Chukchi and Southern Beaufort Seas, and because of unexpectedly short ice-free seasons in Hudson Bay and less multiyear ice in the Canadian Arctic Archipelago.
UPDATE 21 September (10:20 PT): NSIDC has just announced the Arctic sea ice extent minimum (preliminary) for 2020 at 3.74 mkm2 reached on 15 September. See full report here.