Here is a quick compare and contrast of sea ice habitat for polar bears in Canada and the Southern Beaufort region of eastern Alaska near the end of June, 2012-2020.
Similarities between Hudson Bay ice/open water in the sea ice charts below are striking. Ice cover at the end of June shown in these charts since 2012 reinforces the fact, documented in the peer-reviewed literature, that there has been no continued declining trend in dates of sea ice breakup for Western and Southern Hudson Bay since 1998 at least (Castro de la Guardia et al. 2017; Lunn et al. 2016). WH bears are still on the ice.
As a consequence, recent declarations of impending doom for Hudson Bay polar bears, based on claims of reduced population size and health of these subpopulations – which in any case are statistically insignificant for WH and SH (Obbard et al. 2018; Dyck et al. 2017) – must be due to some other cause (Crockford 2020).
In all areas, winds rather than melt due to increased temperatures drive much of the expansion of open water at this time of year.
Posted in Conservation Status, Population, Sea ice habitat
Tagged Alaska, Beaufort, breakup, Canada, cause and effect, Hudson Bay, melt, polar bear, population decline, sea ice, western hudson bay
No early breakup of Hudson Bay sea ice again this year: there is still extensive thick first year ice over most of Hudson Bay and all female polar bears fitted with tracking collars in Western Hudson Bay are still on the ice:
W Hudson Bay polar bears still out on the ice that’s packed together by winds. AE Derocher, 12 June 2020
Breakup of Hudson Bay sea ice as it relates to polar bear movement to land has been about the same since 1999 (about 2 weeks earlier than in the 1980s) and this year is shaping up to be no different: there is still no declining trend in date of sea ice breakup in Western Hudson Bay despite repeated predictions of imminent doom. An especially ‘early’ breakup year would have bears ashore before 15 June. Last year (2019) the first WH bear onshore was caught on film 5 July and problem bears were not recorded onshore in Churchill until the 2nd week of July.
Posted in Conservation Status, Life History, Sea ice habitat
Tagged breakup dates, declining population, early breakup, Hudson Bay, polar bear, sea ice, threatened, trends, western hudson bay
Here are ice conditions at the end of May, which signals the near-end of the critical spring feeding period for polar bears. This is because young-of-the-year seals take to the water to feed themselves, leaving only predator-savvy adults and subadults on the ice from some time in June onward (depending on the region).
Spring is the critical feeding period for polar bears (Crockford 2019, 2020; Lippold et al. 2020; Obbard et al. 2016):
“Unexpectedly, body condition of female polar bears from the Barents Sea has increased after 2005, although sea ice has retreated by ∼50% since the late 1990s in the area, and the length of the ice-free season has increased by over 20 weeks between 1979 and 2013. These changes are also accompanied by winter sea ice retreat that is especially pronounced in the Barents Sea compared to other Arctic areas. Despite the declining sea ice in the Barents Sea, polar bears are likely not lacking food as long as sea ice is present during their peak feeding period. Polar bears feed extensively from April to June when ringed seals have pups and are particularly vulnerable to predation, whereas the predation rate during the rest of the year is likely low.“ [Lippold et al. 2019:988]
Posted in Life History, Sea ice habitat
Tagged Beaufort, Chukchi, feeding, Hudson Bay, open water, polar bear, polynya, sea ice, seals, spring, summer
The chart below shows what sea ice thickness over Hudson Bay was like at the first week of May in a so-called a ‘good year’ (2019) – when polar bears came off the ice in excellent condition late in the summer and left early in the fall (‘thick first year ice’ is dark green and indicates ice greater than 1.2m thick):
Hudson Bay ice conditions this year appear to be shaping up to be as good or better than last year for polar bears yet specialist researchers and their cheerleaders have still been claiming that bears in this region – Western and Southern Hudson Bay – are doomed because of poor ice conditions. It’s no wonder they still haven’t published the data they’ve been collecting on polar bear body condition and cub survival over the last 15 years or so (Crockford 2020). With most field work cancelled for this year, what’s their excuse for not getting that done?
Arctic sea ice at the middle of winter (January-March) is a measure of what’s to come because winter ice is the set-up for early spring, the time when polar bears do most of their feeding on young seals.
[Mid-winter photos of polar bears are hard to come by, partly because the Arctic is still dark for most hours of the day, it’s still bitterly cold, and scientists don’t venture out to do work on polar bears until the end of March at the earliest]
At 12 February this year, the ice was similar in overall extent to 2013 but higher than 2006.
Polar bears leaping on the backs of belugas off Seal River, in western Hudson Bay, is being falsely promoted by the BBC’s new “Seven Worlds: One Planet” TV special as an unprecedented effect of climate change.
More specifically, the Daily Mail (30 November 2019) this morning quoted the documentary, narrated by Sir David Attenborough, as saying:
‘This extraordinary behaviour has only been recorded here, in this remote corner of North America, and only in the last few years.’
Poppycock. More climate change hyperbole from Attenborough’s seemingly never-ending litany of nonsense that’s easily refuted. There is scientific literature documenting such behaviour in Canada’s far north in the 1980s, which I included in the blog post I wrote about this phenomenon a few months ago (after National Geographic published a similar scare-story), which I have reposted below.
And from the sounds of it, there was no mention in the BBC special that freeze-up along western Hudson Bay was early again this year: for the third year in a row. So if the footage was filmed any time since 2017, the claim of accelerating sea ice loss in this region and bears on land for longer than ever is pure fantasy. PS. Fat bears are not ‘starving’.
Posted in Advocacy, Conservation Status, Life History, Sea ice habitat
Tagged Attenborough, BBC, beluga, climate change, Hudson Bay, hunting, polar bear, sea ice, Seven Worlds One Planet, shore, starving
This is the third year in a row that freeze-up of Western Hudson Bay (WH) ice has come earlier than the average of 16 November documented in the 1980s. Reports by folks on the ground near Churchill confirm polar bears are starting to move onto the sea ice that’s developing along the shore after almost 5 months on land. After five good sea ice seasons in a row for WH polar bears, this repeat of an early freeze-up means a sixth good ice season is now possible for 2019-2020.
Sadly for the tourists, however, it means the polar bear viewing season in Churchill will be ending early this year, just like it did last year and the year before.
Polar bear family on the ice off Churchill Manitoba (taken from a helicopter), courtesy Explore.org
When mothers with cubs are out on the ice (see photo above), it’s pretty certain the mass movement from land to sea ice is well underway because these family units are usually the last to leave.
UPDATE 19 November 2019: Polar Bear Alert report for 11-17 Nov (week 20) confirms that freeze-up is underway, bears are heading out on the ice and problem bears held in the ‘jail’ were released 13 November. See below.
Polar bear researcher Andrew Derocher says it takes four years of good sea ice conditions to recruit a polar bear from birth but implies that 2019 is the first year in decades that conditions for bears have been ‘good’ in Western Hudson Bay. He thinks he can get away with saying this because he hasn’t published any of the data on body weight and body condition he’s collected on these bears over the last 25 years (apparently, whatever funding agency pays for his research does not require him to publish the data he collects).
But independent observations such as dates of ice freeze-up in fall, ice breakup in summer, dates and condition of bears recorded onshore, suggest he’s blowing smoke: at least five out of five of the last sea ice seasons for WH bears have been good. That means we should be seeing more bears in the next official population count.
Posted in Advocacy, Conservation Status, Polar bear attacks, Sea ice habitat
Tagged body condition, breakup, Derocher, fat bears, freeze-up, Hudson Bay, polar bear, sea ice, thriving
Polar bear habitat update for the first week of August 2019 shows there is still more sea ice than average in Hudson Bay, the southern-most area of continuous habitation for this species. That certainly wasn’t part of the predictions of doom, especially since freeze-up in that region for the last two years has also been earlier-than-average which means a shorter ice-free season than we’ve seen for decades.
Despite ice coverage for the Arctic ice as a whole being marginally lower than it has been since 1979 for this time of year, sea ice for the first week of August was also above average around Svalbard in the Barents Sea and higher than the last few years in the Central Arctic, which is a critical summer refugium for polar bears that live in the peripheral seas of the Arctic Ocean, including the Chukchi (see photo below, taken in early August 2018).
Posted in Polar bear attacks, Sea ice habitat
Tagged Central Arctic, Churchill, facts, Hudson Bay, polar bear, prediction, problem bear, range, sea ice, southern, Svalbard, tagged bears
For all the hand-wringing over sea ice extent this year and its supposed similarity to 2012, what is truly remarkable is that at the end of July ice remains adjacent to every single major terrestrial summer refugia known to be important for polar bears. Those refugia sites include (from west to east, starting in the Chukchi Sea): Wrangel Island, western Chukotka, Severnaya Zemlya, Franz Josef Land, East Greenland, virtually all the islands of the Canadian Arctic Archipelago (including Southampton Island in Foxe Basin and the southwest and eastern coasts of Baffin Island), and Western Hudson Bay.
Few bears spend the entire summer onshore along the Alaska coast: most still spend the summer on the sea ice and move with it as it contracts toward the Arctic Basin, as do many bears in the Barents, Kara, East Siberian, and Chukchi Seas. Until a few weeks ago, however, there was enough ice present that Beaufort Sea bears could go ashore if they wanted to do so. Continue reading
Posted in Advocacy, Conservation Status, Population, Sea ice habitat
Tagged 2012, Churchill, extent, facts, Hudson Bay, July, onshore, polar bear, problem bears, refugia, sea ice, summer, terrestrial