Posted onMarch 12, 2018|Comments Off on Amstrup & colleages can’t refute my critique of their 2007 polar bear survival model, Part 2
Polar bear specialists Andrew Derocher and Steven Amstrup recently spent inordinate energy trying to refute the opinion piece I’d written for the Financial Post in celebration of International Polar Bear Daylast month, ignoring my fully referencedState of the Polar Bear Report for 2017that was released the same day (Crockford 2018) and the scientific manuscript I’d posted last year at PeerJ Preprints (Crockford 2017).
Their responses use misdirection and strawman arguments to make points. Such an approach would not work with the scientific community in a public review of my paper at PeerJ, but it’s perfect spin for the self-proclaimed “fact-checking” organization called Climate Feedback. The result is a wildly ineffective rebuttal of my scientific conclusion that Amstrup’s 2007 polar bear survival model has failed miserably.
Posted onOctober 1, 2017|Comments Off on Fat healthy polar bear update: hundreds of not-starving bears attracted to dead whale
Are the hundreds of polar bears spending the summer on Wrangel Island in the Chukchi Sea starving and desperate for any scrap of food? Hardly! Photos taken by Russian tourists on a cruise ship (19 September 2017) show a huge number of already-fat, healthy bears converging on a dead bowhead whale washed up on a beach. Most of these bears would have been without food since at least early August, when the last sea ice disappeared around the island, and will return to the ice by November.
The extraordinary sight was witnessed by tourists on an Arctic cruise aboard the Finnish-built MV Akademik Shokalskiy.
A source at Wrangel Island Nature Reserve said: “There were at least 230 polar bears, including single males, single females, mothers with cubs and even two mothers with four cubs each.”
Experts called the sight of so many polar bears together “unique”.
The huge number could in fact amount to as much one per cent of the entire world’s population of the creatures.
Tourists initially thought the bears were a flock of sheep after viewing them from a distance, The Siberian Times reports.
But as the boat drew closer, the lucky holidaymakers realised what they were witnessing.
Fat cubs of the year are seen in the photo below, from the Siberian Timesstory:
A self-proclaimed science-based news site (LiveScience,29 September) that picked up the story of this unique event had the temerity to suggest the bears might have been “hungrier than usual” due to global warming.
It deliberately conflates predictions of future starving bears due to low sea ice levels with this observation of many obviously not-starving bears checking out an attractive food source (my bold):
“It’s unclear, however, whether climate change had made these particular bears hungrier than usual. The frequency of starving polar bears is expected to increase as the climate warms and sea ice declines — not just because of climate change directly, but because ice loss is taking away seals, their main food source, Steven Amstrup, chief scientist at Polar Bears International, a nonprofit research organization dedicated to studying polar bears, told Live Science in 2015.”
Except that there is no evidence that ice loss is “taking seals away” — certainly not in the Chukchi Sea. Chukchi Sea seals have been found to be doing better with less ice than they were when there was more ice in the 1980s.
More below, including the location of Wrangel Island and sea ice maps.
UPDATE 2 October 2017: Sea ice in the Chukchi Sea has been lower this summer than over the last few years but the polar bears spending the ice-free season on Wrangel Island are still in good to excellent condition:
Posted onSeptember 13, 2017|Comments Off on Problem polar bears in Churchill at this date show 2017 less than 2016 and 2015
Comparing Churchill problem bear statisticsover a few years provides some critical perspective: this year, the bears are causing much fewer problems.
This 2nd week in September is no exception, being the 9th week ashore in all cases: 2017 (4-10 September, where I think “total number of polar bear occurrence reports to date” should be 64, not 53, see week 7 reporthere), 2016 (5-11 September), 2015 (7-13 September), where there were about 1/2 the number of bears in “jail” this year compared to the last two years (i. e., 6 vs. 11 and 12) and slightly more than 1/2 the number of occurrence reports in 2017 than in 2016 and 2015 (64 vs. 107 and 99):
Comments Off on Problem polar bears in Churchill at this date show 2017 less than 2016 and 2015
Posted onSeptember 10, 2017|Comments Off on Problem bear reports confirm Churchill polar bears are in excellent condition
Now that all bears are ashore for the season, the folks at the Polar Bear Alert program in Churchill note in their report for week 7 (21-27 August, 2017) that the bears ashore are in excellent condition(confirming reports on the first bears ashore in July):
Rather marked contrast to the pessimistic spin on conditions from the field a few months ago:
[yes, a few bears fail to make it through the winter, especially young bears; but that has always been the case — it’s not a sign of human-caused global warming catastrophe]
Last week’s problem bear report also confirmed news from theChurchill Polar Bearswebsite a few weeks ago that showed several images of very fat bears:
See below for last year’s report for week 7 and this year’s report for week 8 (28 August-3 September). Western Hudson Bay polar bears that come ashore near Churchill, Manitoba are starting their third month on land this week, out of the five months or so they have spent ashore in recent years (about 3 weeks more than in the 1980s, no longer than they did in 2004 — conditions have not been getting worse).
Posted onFebruary 9, 2017|Comments Off on New paper updates lack of trend in W Hudson Bay breakup/freeze-up dates to 2015
A newly-published paper shows that there has been no trend in the time Western Hudson Bay polar bears spent onshore between 2001-2015 due to sea ice conditions at breakup or freeze-up (previously available to 2010 only), despite the marked decline of global sea ice since 2007.
Figure 3 from Castro de la Guardia and colleagues (2017) showing freeze-up and breakup dates and ice-free days 1979-2015 for Western Hudson Bay. Figure with caption, copied below, explains symbols.
Previously, a 2007 paper by Eric Regehr and colleagues for WHB bears up to 2004, which was used to support the US bid to list polar bears as ‘threatened’ with extinction, concluded that between 1984 and 2003, bears were spending 3 weeks longer onshore than they did in the 1980s.
The big news from Castro de la Guardia et al. (2017) is that polar bears spent longer onshore from 1979-2015 by … 3 weeks. That is, no change from the situation in 2004. Wow!
Note the population size of the entire WHB subpopulation has also not declined since 2004 and is currently estimated at about 1030, based on a 2011 aerial survey (Stapleton et al. 2014).
Thanks to Andrew Derocher for the heads-up tweet.
From our research: period W. Hudson Bay #polarbears are onshore increased from ca. 107 to 130 d from 1979 to 2015. Not good for the bears. pic.twitter.com/w90px6XALA
We found that the ice-free period in this region lengthened by 3 ± 0.8 wk over the period 1979−2015. Polar bears migrated onshore 2 wk earlier and offshore 1 wk later in the period 2005−2015 than in 1980−1989.
Here is the region in question, illustrated by Fig. 1 from the paper:
The significant information contained in this paper is breakup and freeze-up dates and length of the ice-free period data for 2010-2015, which has been unavailable until now. More excerpts and comments below, including Figure 3 with its caption. Continue reading
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Posted onOctober 13, 2016|Comments Off on Arctic sea ice grows & Churchill polar bears into their 4th month of fasting
A quiet year for problems in the polar bear capital of the world (Churchill, Manitoba) so far – despite this year tying for the second-lowest minimum since 1979 – and the ice is growing fast. In fact, Arctic ice growth in the second half of September was rapid and there is now more ice than there was at this date in 2007 and 2012 (when polar bears in those regions considered most at risk did not die off in droves).
Posted onOctober 2, 2016|Comments Off on Polar bear onshore in Tuktoyaktuk got so close to kids they heard it breathing
A report from the CBC this morning (with video) of a large polar bear wandering about the village of Tuktoyaktuk on the (Canadian) shore of the Eastern Beaufort Sea on Thursday (29 September) that got very close to a group of children playing outside. Fortunately, no one was hurt.
That this was a rare event is evident in the awe and excitement in the voices of the residents as someone recorded the movements of the bear through town (picture quality is not the best, but clear enough).
As I’ve said before, with more bears we can expect more interactions with people and more sightings like this that haven’t happened in decades. Map and quotes below. Continue reading
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Posted onSeptember 23, 2016|Comments Off on Polar bears seldom catch seals they stalk in summer – it’s why they fast
This short BBC video shows why polar bears are so often unsuccessful in their summer hunts – adult bearded seals are the species most often available on the ice. These seals are not only predator-savvy but there are lots of escape routes in the melting ice, and this has always been so.
“Hungry polar bear surprises a seal – The Hunt: Episode 2 Preview – BBC One”
Melting ice in summer is not a new phenomenon (e.g. NASA photo below from mid-July 2016) – Thomas Grenfell and Gary Maykut described the process of melt pond development back in the 1970s:
“Melt ponds reach the maximum extent shortly after the disappearance of the snow, when they may cover upwards of 50% of the ice.”
Melting summer ice has always made it challenging for polar bears to catch seals, as this quote from Ian Stirling (1974) show, based on his work in the Central Canadian Arctic in the summer of 1973 (July and August):
“There is a great abundance of natural holes in the ice during summer, anyone of which a seal could surface through.“
This is still true in areas like the Southern Beaufort Sea today (e.g. Whiteman et al. 2015): the ice melts and in some areas, disappears completely in summer.
It’s why polar bears – unlike other species of bears in summer – depend on their stored fat to see them through until the ice reforms in the fall.
[When polar bear scientists say “sea ice” or “ice” – they mean summer sea ice. Sea ice in winter and spring are not predicted to decline by 2100 to any appreciable degree and that has been true since sea ice predictions began]
Posted onSeptember 7, 2016|Comments Off on Tracking polar bears in the Beaufort Sea during August 2016
Only three females with collars are still being tracked by USGS researchers in the Beaufort Sea and all of them spent August 2016 on the sea ice in the eastern portion, off the coast of Banks Island.
Meanwhile, as Arctic sea ice nears the annual low, NSIDC predicts that 2016 will likely not set a new record but may bottom-out below 2007 (the second-lowest since 1979). The impact of low September sea ice on polar bear health and survival, based on recent research reports, will be the topic of an upcoming post. Continue reading
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Posted onAugust 30, 2016|Comments Off on Most polar bears easily deterred this time of year, lucky Labrador boaters discover
A polar bear female accompanied by a cub recently attempted to board a small sailboat anchored in a remote harbour off central Labrador – giving the two American boaters below deck a mighty big surprise.
‘He said ‘it’s a bear, it’s right on the boat, make some noise.'” – Nancy Zydler
The encounter occurred south of the same national park where a much-publicized attack occurred in July 2013 (see previous posts here and here) but had a happier ending. See more below from a CBC report released this morning (based on a radio interview) and some ecological context for the sighting not mentioned by the reporter. Continue reading
Comments Off on Most polar bears easily deterred this time of year, lucky Labrador boaters discover
Watch polar bear habitat reform in the Canadian Arctic: “last 10 days” Canadian Ice Service animation (works anytime) HERE.
See Quote archive for details.
A self-proclaimed science-based news site (LiveScience,
The significant information contained in this paper is breakup and freeze-up dates and length of the ice-free period data for 2010-2015, which has been unavailable until now. More excerpts and comments below, including Figure 3 with its caption. 
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