In this newsletter:
Daily Mail, 17 June 2022
Polar Bear Science, 16 June 2022
3) State of the Polar Bear 2021: Arctic bears continue to thrive
Global Warming Policy Foundation, 26 February 2022
4) The Polar Bear Catastrophe That Never Happened
Global Warming Policy Foundation, March 2019
Full details:
1) Scientists discover population of polar bears thriving in the ice-free sea as animals adapt to rising temperatures
Daily Mail, 17 June 2022
While polar bears are often used as the poster child for climate change, a new study has cast doubt on whether rising temperatures will really kill off the animals.
Researchers from the University of Washington have discovered a new population of polar bears thriving in the ice-free sea in Southeast Greenland.
The population is genetically distinct and uniquely adapted to the ice-free environment – and could help to shed light on the future of the species amid rising temperatures.
'Polar bears are threatened by sea ice loss due to climate change,' said Dr Kristin Laidre, who led the study.
'This new population gives us some insight into how the species might persist into the future.
'But I don't think glacier habitat is going to support huge numbers of polar bears. There's just not enough of it. We still expect to see large declines in polar bears across the Arctic under climate change.'
The population has access to sea ice for four months of the year – from February to late May.
During the other eight months, the polar bears hunt seals from chunks of freshwater ice breaking off the Greenland Ice Sheet.
'The marine-terminating glaciers in Southeast Greenland are a fairly unique environment,' said co-author Twila Moon.
'These types of glaciers do exist in other places in the Arctic, but the combination of the fjord shapes, the high production of glacier ice and the very big reservoir of ice that is available from the Greenland Ice Sheet is what currently provides a steady supply of glacier ice.'
Based on historical records and Indigenous knowledge, the researchers knew there were some bears in Southeast Greenland.
However, until now, the region hasn't been studied in detail because of its unpredictable weather, jagged mountains, and heavy snowfall.
'We wanted to survey this region because we didn't know much about the polar bears in Southeast Greenland, but we never expected to find a new subpopulation living there,' Dr Laidre said.
'We just didn't know how special they were.'
In the study, the team combined 36 years of movement, genetic and demographic data to assess the population for the first time.
Their results showed that this group is comprised of a few hundred bears and is genetically distinct from any of the 19 previously known polar bear populations.
'They are the most genetically isolated population of polar bears anywhere on the planet,' said co-author Professor Beth Shapiro.
'We know that this population has been living separately from other polar bear populations for at least several hundred years, and that their population size throughout this time has remained small.'
Body measurements suggest that the adult females are smaller than other regions, and have fewer cubs, which may reflect the challenge of finding mates in the complex environment, according to the team.
Satellite tracking of adult females within the population shows that the bears are homebodies – unlike most other polar bears, who travel far over sea ice to hunt.
This group walks on ice inside protected fjords, or scramble over mountains to reach neighbouring fjords over the Greenland Ice Sheet, according to the team.
Of the 27 bears tracked, half accidentally floated an average of 120 miles south on small ice floes caught in the East Greenland coastal current, before hopping off and walking home on land.
'In a sense, these bears provide a glimpse into how Greenland's bears may fare under future climate scenarios,' Dr Laidre said.
'The sea ice conditions in Southeast Greenland today resemble what's predicted for Northeast Greenland by late this century.'
The population has access to sea ice for four months of the year – from February to late May.
During the other eight months, the polar bears hunt seals from chunks of freshwater ice breaking off the Greenland Ice Sheet.
'The marine-terminating glaciers in Southeast Greenland are a fairly unique environment,' said co-author Twila Moon.
'These types of glaciers do exist in other places in the Arctic, but the combination of the fjord shapes, the high production of glacier ice and the very big reservoir of ice that is available from the Greenland Ice Sheet is what currently provides a steady supply of glacier ice.'
The findings raise hope that polar bears could be adapting to survive amid rising global temperatures.
'If you're concerned about preserving the species, then yes, our findings are hopeful — I think they show us how some polar bears might persist under climate change,' Dr Laidre said.
Polar Bear Science, 16 June 2022
NASA photo, SE Greenland glacier-front habitat with a polar bear and two cubs.
Previously, polar bear researchers simply assumed all of the bears in East Greenland were part of the same subpopulation but no field work had been conducted in the extreme southern area until 2015-2017. When they included this region, they got they got a big surprise: now they are spinning it as significant for polar bear conservation (Laidre et al. 2022).
From a new paper by Kristin Laidre and colleagues today in the journal Science, the map below shows this newly-defined population in red in SE Greenland (south of 64 degrees N), which is known as the King Frederick VI Coast:
Apparently the few bears found on the southwestern tip of Greenland, near the former Norse ‘Eastern Settlement’ (dark blue in the above map) do not belong to this new subpopulation, which means that recent problems on the SW tip of Greenland–including a horse that was killed in the winter of 2016–cannot be blamed on members of this new subpopulation.
My own work on ancient polar bear remains did not reveal any archaeological specimens from that region (Crockford 2022). There are only a few known ancient Inuit sites in the area, primarily around Timmiarmiit.
Danish naval officer Wilhelm August Graah explored the SE coast in 1828-30 while looking for the lost Norse Eastern Settlement and, having rounded the tip at Cape Farewell, described the now-extinct SE Greenland Inuit (Graah 1837). In 1929, he named the region the King Frederick VI Coast but was prevented from travelling further than the area of Koge Bay (see map above) by thick pack ice.
Currently, the largest community on the SE coast is further north, at Tasiilaq, but the realm of SE Greenland polar bears is currently uninhabited by humans. Few hunters venture so far south, even temporarily.
The New Population
This newly-discovered population of SE Greenland bears apparently uses marine-terminating glacier fronts (including calved pieces of freshwater glaciers) that exist in deep coastal fjords as platforms to hunt ringed seals when the land-locked fast ice disappears. As they also do in Svalbard, some ringed seals use glacier-front habitat year round, likely because the presence of ice generates upwelling of nutrients and thus, fish to eat (Hamilton et al. 2016, 2017). In other words, ringed seals and polar bears throughout the Arctic are almost certainly capable of utilizing glacier-front habitats where ever they occur, as they have been doing in SE Greenland.
According to the authors:
"Southeast Greenland bears appear to have adapted their movements to the region’s specific physical geography. The high-velocity East Greenland Coastal Current (12) seasonally brings a narrow band of low-concentration pack ice south of 64°N and around the southern tip of Greenland (figs. S8 to S10) (13). All tracked Southeast Greenland bears that moved out of the fjords (n = 11) became caught in this current’s drift ice and were transported southward toward Cape Farewell, drifting an average of 189 km in <2 weeks (fig. S4). Notably, all swam ashore and walked via land to their home fjord within 1 to 2 months, demonstrating high site fidelity. Bears in Southeast Greenland must remain inside fjords or risk export to human inhabited areas of South Greenland or into the North Atlantic." -- Lairdre et al. 2022:1333.
However, the genetic data also indicate the subpopulation has been separate for only about 200 years (189-264). This suggests to me the possibility that the thick ice at around 65 degrees N that stopped the northward travel of Graah in 1829 mentioned above may have been a decades-long phenomenon that also trapped polar bears on the SE coast and kept them entirely separate from NE Greenland bears until very recently. The authors did not mention this as a possibility: in fact, they didn’t provide any explanation at all for why the populations became separated about 200 years ago or comment why such distinctive genetic signatures would be evident after such a short period of evolutionary time.
Of course, the authors suggest this new subpopulation–although unnoticed by them for decades while easily surviving an ice-free period similar to conditions predicted for the High Arctic in the late 2100s–must be conserved to protect the genetic diversity of the species (Peacock 2022). In other words, they see it primarily as welcome additional pressure to protect polar bears from global warming.
Peacock concludes [my bold]:
"It is unclear whether the Agreement [1973 International Agreement to Protect the Polar Bear], which had been so successful in bringing back the global populations from overharvest, will be an adequate mechanism to protect polar bears in the face of reduced habitat due to climate change. The population of southeast Greenland is a small, genetically distinct group of bears with a distinctive ecology. In the conservation of this polar bear population, we find an explicit test of the modern influence of the half-century-old international Agreement on the Conservation of Polar Bears." Peacock 2022: 1268
I truly appreciate Lily Peacock’s acknowledgement that polar bear numbers have indeed increased since the 1960s, as I have been criticized for pointing that out (Crockford 2017, 2019; Crockford and Geist 2018). Leaving aside all the pointless hand-wringing about impending doom based on implausible climate models, the existence of this new subpopulation is interesting but hardly a game-changer.
In two papers and several press releases, there is no mention of the fact that polar bears in general were savvy and flexible enough to have survived through several warm interglacials that were warmer than today (Cronin et al. 2014; Cronin and Cronin 2015) or that many Svalbard bears recently moved onto the sea ice or to Franz Josef Land when sea ice on the west coast of the archipelago became scarce (Aars et al. 2017; Andersen et al. 2012; Crockford 2019).
Bottom line: I’m OK with 20 subpopulations of polar bears and satisfied that adding SE Greenland to the mix, separate from NE Greenland, is the right thing to do. I’m thrilled to see evidence that glacier-front habitat can support a small polar bear population even without summer sea ice. Now let’s see the population size estimate for all of East Greenland we’ve been waiting to see for more than ten years (Laidre et al. 2012). Are there only about 600 bears (as one PBGS estimate put it) or about 2,000 (the ball-park estimate used by the 2015 Red List assessment)? Or are there even more?
Full post & references
3) State of the Polar Bear 2021: Arctic bears continue to thrive
Global Warming Policy Foundation, 26 February 2022
Crockford further clarifies that the global population estimate used by the PBSG has not been updated since 2015, even though the results of numerous surveys have been published since then.
These additions bring the global population total to almost 32,000, up from about 26,000, albeit with a wide range of potential errors.
This modest increase is consistent with a species recovering from low numbers brought about by overhunting after focused international protection was introduced in 1973.
In 2021, results of an aerial survey of the Chukchi Sea in 2016 generated a population estimate of 5,444 (range 3,636–8,152), about 2,500 greater than a previous survey but within its range of error.
This estimate is in line with other evidence that conditions for polar bears in the area have been excellent.
Results from a 2017–2018 survey of the Davis Strait subpopulation published in 2021 revealed numbers were stable, although the bears were fatter than they had been in 2005-2007, with good cub survival indicating a thriving population.
Dr. Crockford reports that there were three serious attacks by polar bears on people in 2021 but no fatalities.
She explains that there were no reports of widespread starvation of bears, acts of cannibalism, or drowning deaths that might suggest bears were having trouble surviving the ice-free season.
“The current health and abundance of polar bears continue to be at odds with predictions that the species is suffering serious negative impacts from reduced summer sea ice blamed on human-caused climate change.”
Full report - Susan Crockford: State of the Polar Bear 2021 (pdf)
4) The Polar Bear Catastrophe That Never Happened
Global Warming Policy Foundation, March 2019
Researcher says attempts to silence her have failed
Polar bear numbers could easily exceed 40,000, up from a low point of 10,000 or fewer in the 1960s.
In The Polar Bear Catastrophe that Never Happened, a book published today by the Global Warming Policy Foundation, Dr Susan Crockford uses the latest data as well as revisiting some of the absurd values used in official estimates, and concludes that polar bears are actually thriving:
"My scientific estimates make perfect sense and they tally with what the Inuit and other Arctic residents are seeing on the ground. Almost everywhere polar bears come into contact with people, they are much more common than they used to be. It’s a wonderful conservation success story."
Crockford also describes how, despite the good news, polar bear specialists have consistently tried to low-ball polar bear population figures.
They have also engaged in a relentless smear campaign in an attempt to silence her in order to protect the story of a polar bear catastrophe, and the funding that comes with it.
A few unscrupulous people have been trying to destroy my reputation”, she says. “But the facts are against them, and they have failed”.
The Polar Bear Catastrophe that Never Happened — published by the Global Warming Policy Foundation
Available in paperback
or Kindle ebook
About the book
The Polar Bear Catastrophe That Never Happened explains why the catastrophic decline in polar bear numbers we were promised in 2007 failed to materialize. It’s the story of how and why the polar bear came to be considered ‘Threatened’ with extinction, and tracks its rise and fall as an icon of the global warming movement. The book also tells the story of Crockford’s role in bringing that failure to public attention and the backlash against her that ensued – and why, among all others who have attempted to do so previously, she was uniquely positioned to do so. In general, this is a cautionary tale of scientific hubris and of scientific failure, of researchers staking their careers on untested computer simulations and later obfuscating inconvenient facts. For the first time, you’ll see a frank and detailed account of attempts by scientists to conceal population growth as numbers rose from an historical low in the 1960s to the astonishing highs that surely must exist after almost 50 years of protection from overhunting. There is also a blunt account of what truly abundant populations of bears mean for the millions of people who live and work in areas of the Arctic inhabited by polar bears.
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