Polar bear biologist Andrew Derocher published a tracking map of his collared polar bear females that shows one bear (out of 11) still on the rapidly diminishing ice north of Churchill in Western Hudson Bay – and where there is a collared female, there is almost certainly other bears doing the exact same thing:
Without evidence to support such a claim, Derocher (below) assumes this collared female is probably hunting seals. In fact, last year he admitted that most bears on Hudson Bay from at least July onward are unlikely to be successfully hunting seals:
Contrary to all expert expectations, five female polar bears (45%) out of eleven that had tracking collars attached last year were still out on the sea ice that’s lingering along the western shore of Hudson Bay as of 7 August. And if five collared bears are out there, then there are almost certainly many more without collars doing the same thing. This pattern of bears staying out on the ice long after the so-called ‘critical threshold’ of 50% concentration has passed has been going on since at least 2015 and many bears on tracking maps in July and August appear to be on ice that doesn’t exist.
There are two explanations for this pattern and both are likely true: 1) much more ice actually exists on Hudson Bay than satellites can detect and 2) polar bear experts are wrong that Western Hudson Bay polar bears head to land soon after sea ice concentration drops below 50%. Models that predict a catastrophic future for Western Hudson Bay polar bears (Castro de la Guardia et al. 2013; Molnar et al. 2020) assume that ice coverage of less than 50% in summer greatly reduces polar bear survival. However, if polar bears do not always head to land when sea ice drops below 50% then the models cannot possibly describe their future accurately. In other words, depending on the discredited ‘worst case’ RCP8.5 climate scenario for the most recent polar bear survival model that extrapolates from Western Hudson Bay bear data to many other subpopulations, as I discussed previously, may not be its only fault.
Posted in Conservation Status, Life History, Sea ice habitat
Tagged assumptions, behavioural plasticity, breakup, contradictions, extinction, Hudson Bay, melt ponds, polar bear, predictions, RCP8.5, sea ice, western hudson bay
In something resembling a new pattern for Western Hudson Bay polar bears, most of the animals are still out on the ice in late July this year, just like they were in the 1980s. The same thing happened last year but was brushed off as a happy anomaly. However, after last fall’s 1980s-like early freeze-up, this makes the sixth year in a row of good to very good sea ice conditions for Western Hudson Bay polar bears. No wonder polar bear experts haven’t published these data: good sea ice conditions along with polar bears coming ashore fat and healthy are not just inconvenient – they threaten to destroy the extinction panic narrative that depends on Western Hudson Bay bears showing evidence of harm from reduced sea ice.
Fat mother and cub onshore at Wakusp National Park, Western Hudson Bay 18 July 2020, one of the first of the season.
Posted in Advocacy, Life History, Sea ice habitat
Tagged breakup, catastrophe, extinction, good years, Hudson Bay, models, polar bears, prediction, proxy, sea ice, trends, western hudson bay
This updated blog post of mine from last year is as pertinent now as it was then: it’s a fully-referenced rebuttal to the misleading ‘facts’ so often presented this time of year to support the notion that polar bears are being harmed due to lack of summer sea ice. Polar Bears International developed ‘Arctic Sea Ice Day’ (15 July) to promote their skewed interpretation of polar bear science at the height of the Arctic melt season. This year I’ve add a ‘Polar Bears and the Arctic Food Chain‘ graphic, which readers are free to download and share. For further information, see “The Polar Bear Catastrophe That Never Happened“.
Posted in Conservation Status, Life History, Sea ice habitat, Summary
Tagged Arctic, Arctic sea ice day, facts, feeding, hunting, misinformation, myths, polar bear, sea ice, spring, summer, survival
Don’t expect to hear this news from polar bear activists busy promoting the supposed threat to polar bears from declining Arctic sea ice but ice cover over Hudson Bay so far this summer has been very similar to what it was in the 1980s – often promoted as ‘the good old days’ for Western Hudson Bay polar bears. As of the end of June 2020, very concentrated ice (9/10-10/10) more than 1 metre thick still covered most of the bay and there was still no open water near Churchill along the west coast down into James Bay.
Polar bear activists don’t like to have current Hudson Bay sea ice reality ruin their social and news media narrative that ‘polar bears are all gonna die’, so they instead emphasize the obsolete ‘declining trend’ for Western Hudson Bay breakup dates that haven’t been updated since 2015 (e.g. Castro de la Guardia et al. 2017; Lunn et al. 2016). They do this despite the fact their colleagues admit polar bears don’t catch many seals after late June (regardless of sea ice conditions) because it is past the peak spring feeding period (Obbard et al. 2016; Lippold et al. 2019). Like in the 1980s, in 2015 and 2019 some bears stayed on the ice until early August and 2020 is shaping up to be another 1980’s-like summer.
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 report on the latest population estimate for harp seals off the east coast of North America was released in late March without fanfare and therefore no media attention. This was one of the missing scientific reports mentioned in my State of the Polar Bear Report 2019 released in February (Crockford 2020): results of surveys promised for months or years by early 2020 but not delivered.
Not surprisingly then, we find the report has good news: the population estimate of harp seals in the NW Atlantic has risen to about 7.6 million (range 6.55-8.82) animals (DFO 2020), up from 7.4 million in 2014 (DFO 2014).
Note that the survey was done in March 2017, a low ice year for the Gulf of St. Lawrence (see discussion below) and while this may have resulted in some increased mortality for pups born there, it is also known that many ‘Gulf’ pregnant females will instead have given birth off Newfoundland and Labrador in a whelping region called ‘The Front’. Apparently, these factors were accounted for in the population model.
Harp seal pups born at the Front are an important food for Davis Strait polar bears. This increase in the prey base for Davis Strait polar bears suggests the bear population may have grown substantially since the last survey in 2007 (Peacock et al. 2013; Rode et al. 2012). Davis Strai is the only subpopulation of polar bears officially considered to have ‘likely increased’ at 2018 by Environment Canada. A new Davis Strait population size survey was apparently completed in 2018 but the results are not yet available (Crockford 2020).
Highlights, quotes, and figures from the harp seal report below. Continue reading
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?
A recent paper that attempted to correlate pollution levels and body condition in Barents Sea polar bears reports it found body condition of female bears had increased between 2004 and 2017 despite a pronounced decline in summer and winter sea ice extent.
“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” [Lippold et al. 2019:988]
Posted in academic freedom, Conservation Status, Life History, Population, Sea ice habitat
Tagged Barents Sea, body condition, denier, deplatformed, ice-free season, polar bear, sea ice, summer, Svalbard, threatened, vulnerable