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.
UPDATE 8 November 2020: Report from Churchill area polar bear guide Kelsey Eliasson, via Facebook Saturday 7 November: “Most bears have left on the ice – including peanut – but still some stragglers” [‘Peanut’ is a well-known female who has two cubs this year]. See below for sea ice chart for 8 November shows broadening band of grey ice clearly thick enough to support the weight of adult bears (and the same thing is happening in Southern Hudson Bay):
Posted in Conservation Status, Life History, Population, Sea ice habitat
Tagged breakup, Churchill, computer models, freeze-up, future, Hudson Bay, ice-free season, polar bear, predictions, sea ice
Just in time for Polar Bears International’s self-proclaimed fall Polar Bear Week (5-11 November 2017), here’s a new resource for cooling the polar bear spin. I’ve updated my 2015 summary of reasons not to worry about polar bears, which is now more than two years old. In this new version, you will find links to supporting information, including published papers and fully referenced blog posts of mine that provide background, maps and bibliographies, although some of the most important graphs and maps have been reproduced here. I hope you find it a useful resource for refuting the pessimism and prophecies of catastrophe about the future of polar bears. Please feel free to share it.
As global leaders meet in Bonn for COP23 (6-17 November 2017), it’s time to celebrate the proven resilience of polar bears to their ever-changing Arctic environment.
Twenty Reasons: the bullet points
- Polar bears are still a conservation success story: there are more polar bears now than there were 40 years ago.
- Fewer populations are in decline than in 2010 (only one, officially) and only six are data deficient (down from nine).
- Abrupt summer sea ice decline has not affected polar bear numbers as predicted: even though sea ice levels dropped to mid-century levels in 2007, the expected decimation of polar bears failed to occur.
- The Chukchi Sea population is thriving despite a pronounced lengthening of the ice-free season since 2007.
- Less sea ice in the summer in the Chukchi Sea has meant a healthy prey base for polar bears because ringed seals feed primarily in the ice-free season.
- Polar bears have shown themselves to be adaptable to changing ice conditions in several regions.
- Southern Beaufort numbers have rebounded since the last survey count.
- Barents Sea numbers have probably increased since 2005 and have definitely not declined despite much less sea ice cover.
- There is no evidence that record-low summer sea ice in 2012 had a harmful effect on Southern Beaufort bear numbers.
- Other species are being negatively impacted by high polar bear numbers, especially nesting sea birds and ducks.
- Western Hudson Bay population numbers have been stable since 2004, despite what scientists are telling the media.
- Hudson Bay sea ice has not changed since about 1999: breakup dates and freeze-up dates are highly variable but the ice-free period was not any longer in 2015 than it was in 2004. However, this fall freeze-up is shaping up to be the earliest in decades.
- Problem bears in Churchill are not lean or starving.
- Churchill Manitoba had the most problem bears in 1983 and 2016, which were late freeze-up years, but many of the incidents in 2016 can be attributed to increased vigilance on the part of patrol officers after an attack in 2013.
- There have been only marginal sea ice declines during the feeding period in spring, when polar bears need sea ice the most.
- The is no evidence that subsistence hunting is affecting bear populations.
- Stressful research methods have been curtailed in much of Canada.
- There have been no reports of polar bear cannibalism since 2011.
- Polar bears appear unaffected by pollution: studies suggest only that harm is theoretically possible, not that it has happened.
- Polar bears have survived past warm periods, which is evidence they have the ability to survive future warm periods.
- Polar bears are thriving: they are not currently threatened with extinction.
- Tens of thousands of polar bears did not die as a result of more than a decade of low summer sea ice, as was predicted.
- Polar bears don’t need sea ice in late summer/early fall as long as they are well-fed in the spring.
[full text below, pdf with footnotes and references here]
The simple fact is that if polar bear experts had been right about the threat to polar bears from the loss of summer sea ice in the Arctic, there would be no polar bears in Churchill this fall. No bears for tourists to photograph, none for biologists to study, and certainly none for the BBC to film for an upcoming three-part TV special called “Arctic Live.”
The low-ice future that biologists said would doom polar bears to extinction by 2050 has already happened in 8 out of the last 10 years. The sea ice future has been realized.
Polar bears have experienced those supposedly deadly low-ice summers for almost a decade but the global population did not drop by 2/3 as predicted and not a single one of the ten subpopulations predicted to be extirpated under those conditions has been wiped out.
How much more wrong can you be than that? Will the BBC mention this conundrum in their show? Will the polar bear experts they consult share this fact with viewers? We’ll all have to watch and see [show times and summaries of each program here, 1-3 November] but here are some background facts that might enhance your viewing experience.
UPDATE: Sea ice condition of Hudson Bay at 1 November 2016 below from the Canadian Ice Service (some slushy ice looks to be forming along the coast north of Churchill – this is how freeze-up starts). See the animation for the last 10 days here:
Posted in Population, Sea ice habitat
Tagged Arctic Live, BBC, Churchill, extinction, extirpation, facts, future, minimum, observations, polar bear, predictions, resilience, sea ice, September, survival, threatened
Apparently, the IUCN Polar Bear Specialist Group (PBSG) thinks that it’s OK to mislead the public on the conservation status of polar bears for half a year because its website is being revamped. This conservation organization is of the opinion that people landing on their website while searching for official polar bear status information don’t need to know right away that a new IUCN Red List document was published in November 2015. We know this because the message below appeared on the PBSG homepage 14 January 2016 (text in bold was there previously: the new message is in CAPS), screencap of entire page at 16 Jan 2016 pdf here:
It appears that the PBSG feels that the public can wait to be told about 2015 Red List decision until the PBSG are ready for them to be told, which could be anywhere from March to the end of June 2016, depending on what definition of “spring” they use. Anyone (like moi) suggesting this tactic is paramount to withholding unpleasant information is just being “impatient.”
Decide for yourself but to me, this PBSG message speaks volumes: it says the 2015 IUCN Red List assessment is bad news for polar bear predictions of gloom and doom. Polar bear specialists don’t want to talk about it because it is a slap-down of all previous attempts at predicting a grim future for the bears (see the summary at the end of this post).
Posted in Advocacy, Conservation Status, Population
Tagged conservation, Derocher, Encyclopedia of Life, extinction, facts, future, IUCN, misinformation, PBSG, polar bear, politics of polar bears, population trend, predictions, Red list, sea ice, Sherren, status, threatened, Vongraven, vulnerable
A few days ago polar bear biologist Mitch Taylor and Nunavut’s Gabriel Niryungaluk talked to Toronto radio host Roy Green about the recent USGS dire model predictions for the future of polar bears.
There’s an audio podcast and, courtesy of the valuable efforts of fellow blogger Alex Cull, a transcript. Links below, plus some excerpts of Mitch Taylor’s commentary.
Posted in Conservation Status, Population
Tagged Alex Cull, climate change, crystal ball, extinction, future, Gabriel Niryungaluk, global warming, greenhouse gases, imminent danger, Mitch Taylor, models, Nunavut, opinion, polar bear, population size, predictions, radio interview, sea ice, threatened, transcript, USGS
The trouble is, sea ice researchers and atmospheric scientists have not drawn that conclusion, despite what a new paper by Pilfold and colleagues imply. It shows just what lengths desperate IUCN Polar Bear Specialist Group (PBSG) biologists will go to in order to link the recent decline of Southern Beaufort bear numbers to global warming while ignoring similar past declines.
Posted in Advocacy, Life History, Sea ice habitat
Tagged Beaufort Sea, climate change, Derocher, Eastern Beaufort, extinction, feeding, future, global warming, IUCN Polar Bear Specialist Group, models, Pilfold, polar bear, population, predation, predictions, Red list, ringed seals, Southern Beaufort, Stirling, thick spring ice, threatened
Polar bear activist Steven Amstrup made an astonishing statement in an interview earlier this week — he insisted that the current rate of warming in the Arctic is greater than anything polar bears have lived through before. He also said that optimistic comments on the future of polar bears made by geneticist Matt Cronin a few weeks ago were “incautious” and “misleading.”
Previously, I described how a new paper by Cronin and colleagues confirmed that genetic evidence indicates polar bears have been around long enough to have survived several past Interglacial periods that were warmer than today (and therefore, would have had virtually no summer ice). Cronin, not unreasonably, had some critical things to say about computer modeled predictions that polar bears could not survive in an Arctic without summer sea ice.
On Monday, the Anchorage Daily News gave Amstrup a forum to rebuke Cronin for his comments. A similar story was also carried by the Washington Post. [In the same ADN article, geneticist Charlotte Lindqvist, offered an outdated argument against future polar bear survival that I’ll deal with later]
Today, I’ll address Amstrup’s ridiculous assertion that the current rate of warming, attributed by him primarily to human activities rather than natural variation, is something polar bears have never experienced in their evolutionary history (a period of more than 400,000 years!).
Let’s start with the offending portion of the news item (published March 31, 2014):
Posted in Advocacy, Evolution, History
Tagged Amstrup, Anchorage Daily News, Cronin, Eemian, future, global warming, Holocene, interglacial, Lindqvist, misleading, models, past warming trends, polar bear, polar bear resilience, rate of warming