Tag Archives: summer

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.

This is not surprising since even 2nd lowest leaves summer ice coverage in the Arctic at the level sea ice experts wrongly predicted in 2005 wouldn’t be seen until 2050 (ACIA 2005; Amstrup et al. 2007; Wang and Overland 2012) and this is the same amount of summer sea ice that polar bear experts incorrectly predicted would cause 2/3 of all polar bears to disappear. My book explains how it all went wrong: The Polar Bear Catastrophe That Never Happened

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.

Continue reading

Amid crying over low Arctic ice, W Hudson Bay polar bears leave ice as late as 2009

This year, the last collared Western Hudson Bay polar bear to leave the ice left as late, or later, than the last collared bear did in 2009 (which was an unusually late breakup year) and so far, all bears spotted have been in good physical condition despite inhabiting one of the most southern regions of the Arctic. All the while, sea ice experts have been hand-wringing about low Arctic sea ice –– in general and as polar bear habitat.

Polar bear Cape East 0 Wakusp NP _24 Aug 2020 earlier

A female with two yearling cubs on the shore of Wakusp National Park, Western Hudson Bay on 24 August 2020. Taken via livecam from almost a mile away.

Continue reading

10 fallacies about Arctic sea ice & polar bear survival refute misleading ‘facts’

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“.

Polar bear top of Arctic food chain 7 July 2020

Continue reading

Spring feeding season almost over for polar bears & sea ice becomes less important

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).

masie_all_zoom_4km 2020 May 31_Day 152

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]

Continue reading

New Paper: Body condition of Barents Sea polar bears increased since 2004 despite sea ice loss

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.

Svalbard polar bear Jon Aars_Norsk Polarinstitutt

“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]

Continue reading

Sea ice adjacent to all major polar bear onshore summer refugia at 31 July 2019

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.

masie_all_zoom_4km 2019 July 31

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

10 fallacies about Arctic sea ice & polar bear survival: teachers & parents take note

Summer sea ice loss is finally ramping up: first year is disappearing, as it has done every year since ice came to the Arctic millions of years ago. But critical misconceptions, fallacies, and disinformation abound regarding Arctic sea ice and polar bear survival. Ahead of Arctic Sea Ice Day (15 July), here are 10 fallacies that teachers and parents especially need to know about.

Polar_Bear_Summer_2 FINAL (2)

The cartoon above was done by Josh: you can drop off the price of a beer (or more) for his efforts here.

As always, please contact me if you would like to examine any of the references included in this post. These references are what make my efforts different from the activist organization Polar Bears International. PBI virtually never provide references within the content it provides, including material it presents as ‘educational’. Links to previous posts of mine that provide expanded explanations, images, and additional references are provided.

Continue reading

Images from 2017 and 2018 show polar bears thriving in a warming world

Candid images of fat, healthy bears taken over the last two years by unbiased photographers across the Arctic are representative of the state of polar bears in a world that’s warmer than it was in 1980.


Chukchi Sea polar bear on the sea ice, early August 2018. A Khan, NSIDC. Chukchi Sea bears are thriving, according to a new survey of the population.

It may seem counter-intuitive but it’s true: polar bears are thriving with less summer sea ice and there are more bears now than there were in 2005 (not a statistically significant amount more, but more nevertheless).

Continue reading

Now at least 10 years with sea ice at 2050-like levels yet polar bears are still abundant

We’ve hit the seasonal Arctic sea ice minimum for this year, called this morning by US NSIDC for 19th and 23rd of Septmeber: 4.59 mkm2, the same extent as 2008 and 2010. This is not a “ho-hum” year for polar bears: it means that since 2007, they have triumphed through 10 or 11 years1 with summer ice coverage below 5.0 mkm2 —  levels that in 2007 were expected to cause catastrophic declines in numbers.


Summer sea ice below 5.0 mkm2 were not expected to occur until about 2050, according to 2005/2006 sea ice models and polar bear specialists at the US Geological Survey (USGS). Polar bear survival models predicted 2/3 of the world’s polar bears would disappear when ice levels reached this threshold for 8 out of 10 years (Amstrup et al. 2007, 2008; Hunter 2007) but polar bears have been more resilient than expected (Crockford 2017, 2018; Crockford and Geist 2018). In fact, in many areas (like the Chukchi Sea, Barents Sea and Foxe Basin) polar bears are thriving despite dramatic declines in summer sea ice coverage (Aars et al. 2017; ACSWG 2018; Peacock et al. 2013; Regehr et al. 2016; Stapleton et al. 2016).

The sea ice models used to support the addition of polar bears to the US Endangered Species List as ‘threatened’ with extinction suggested sea ice levels from 3-5 mkm2 would not occur unti mid-century, yet they dropped before the ink was dry on the 2007 USGS Reports (ACIA 2005; Hassol 2004; Holland et al. 2006; Solomon et al. 2007; Zhang and Walsh 2006).

The ice extent charts from the University of Bremen (below) show ice that’s 50% concentration or greater at the date of the seasonal minimum (19th September): what polar bear specialists define as preferred habitat (Amstrup et al. 2007).


Compare the minimum shown above to the coverage predicted for 2050 and to coverage at the minimum in 2012 (the NSIDC image is here):

Continue reading

Brace yourself: more starving polar bear news stories in the pipeline from Svalbard

A few polar bears have become stranded on small islands north of Svalbard since the local sea ice retreated — of which the bear that mauled a cruise ship guard last month was but one — and if return of the ice is as late as last year, those handful of bears are likely doomed to die of starvation. This is not due to climate change but rather bad judgment on the part of these few bears. They were not forced ashore: if they’d stayed on the ice like the rest of the population, they’d have likely been just fine.

Daily Mail stranded bear headline_3 Aug 2018 all

Similar to the bear in northwestern Hudson Bay that fatally mauled a young father in early July, these bears were likely lured ashore by the prospect of masses of bird eggs present on island rookeries. But they overstayed their window of opportunity and the ice retreated without them.

Fledgling birds and bird eggs are not replacements for seals in a bear’s diet but when the season of easy seal kills winds down, as it does in late spring, easy-picking sea bird eggs may be enticing enough to lure a few bears ashore when they’d be better off on the ice.

That is not the fault of climate change.

Unlike bears in Hudson Bay and many other regions — including the Lancaster Sound area of Canada where the National Geographic “starving” bear was filmed last summer — these bears were not forced ashore by retreating ice: they chose to do so.
Continue reading