Contrary to what the misleading press release implies, an entirely speculative new paper by polar bear specialists Kristin Laidre and Ian Stirling (among others) presents zero evidence that polar bear consumed whale carcasses during the last warm Interglacial (Eemian, ca. 115-130kya). And contrary to the impression that Eemian conditions were very challenging for polar bears, simulations from the single paleo sea ice simulation paper these authors cite show the ice-free season over most of the Eemian was less severe than today in the polar basin, with no reason for polar bears to scavenge extensively on large whale carcasses.
Polar bears are shown scavenging on the carcass of a dead bowhead whale that washed ashore on Wrangel Island, Russia. Credit: Chris Collins/Heritage Expeditions
This is yet another paper posing as science co-authored by Stirling that uses anecdotal accounts of behaviour to send a message about evolutionary capabilities of polar bears (Stirling and van Meurs 2015). With little or nothing to back it up, the paper’s real purpose is to convey Stirling’s opinion that past polar bear survival is irrelevant to understanding future polar bear survival — and that all the bears are gonna die unless we do something about carbon dioxide emissions generated by fossil fuel use.
Is it a coincidence that the Summary for Policy Makers was issued by the IPCC over the weekend (not the report with the science in it but the document that all politicians agreed were acceptable)? Look no further than the last sentence of National Geographic’s article on this story, which includes a quote from lead author Laidre and a link to the magazine’s interpretation of the new IPCC report:
“Laidre put it even more bluntly: “If you want polar bears around we need sea ice, and loss of sea ice closely tied to our activities and our fossil fuel emissions.” (Learn about the IPCC’s dire new climate report.)”
Posted in Advocacy, History, Life History, Sea ice habitat
Tagged anecdotal observations, carcasses, dead whales, Eemian, interglacial, models, polar bear, sea ice, whales
A press release issued yesterday (23 January 2018) by the University of Stavanger tells the story of decades of work on the most complete ancient polar bear skeleton in the world, found in 1976 in southern Norway, that culminated in an articulated museum display. This specimen was described in my research paper, Annotated Map of Ancient Polar Bear Remains of the World (Crockford 2012), which shows how many very early Holocene remains have been found outside current polar bear range.
Posted in Evolution, History, Sea ice habitat
Tagged ancient, archaeology, bones, fossils, geology, Holocene, ice age, Norway, polar bears, range, sea ice, skeleton, Younger Dryas
Churchill, Manitoba’s Polar Bear Alert Program is still reporting many fewer problems with polar bears onshore than it did last year at the same point in the ice-free season (week 5, 7-13 August):
Compare to week five last year (2016), when bears came ashore in excellent condition:
Although it’s been warmer than average recently (25.4 degrees C yesterday, expected to reach 29 degrees C today and 28 degrees C tomorrow), according to Environment Canada weather records, that’s not even close to an August record-breaker temperature for Churchill. Continue reading
Posted in History, Life History, Polar bear attacks
Tagged alert, attacks, Churchill, encounters, facts, heat wave, history, ice-free, jail, onshore, polar bear, problems, temperature
A story that broke in Alaska newspapers a month ago made the UK press this weekend about the archaeological discovery of 1,300 year old polar bear skull that may be associated with an unusual body type known to Inuit hunters. See the Mail Online cropped headline below, full story here – and some quotes and critical background below.
Posted in History, Life History
Tagged ancient, archaeological remains, body type, genetics, history, king bear, polar bear, race, subspecies, weasel bear
A part-time Arctic researcher eager for media attention suggested earlier today that the ice entrapment of narwhals in 2008 and again in 2015 at Pond Inlet (that made headlines around the world) was the result of “sudden changes in temperature” caused by climate change. This grossly misleading claim ignores the facts: ice entrapment of narwhals is an entirely natural feature of the Arctic that has been known about for hundreds of years.
“Narwhals: the ‘giant unicorn of the sea’ at risk from climate change” (CBC, 13 August 2016), a print version of a CBC Radio interview with Clint Wright that aired 8 August 2016. Wright is the general manager at the Vancouver Aquarium and apparently has “joined a team of researchers to tag and study” narwhals for several years – but does not seem to know much about the history or circumstances of natural ice entrapment.
Ice entrapment of small whales is nothing new. The first formally documented incident – in English – occurred in 1915 (Porsild 1918) and the phenomenon has probably occurred as long as there has been ice in the Arctic (millions of years).
Animals routinely become trapped in a few specific areas due to local geography: when ice that forms in the north moves south quickly, it blocks the entrances to inlets or coastal bays that still have open water. The presence of the pack ice causes nearby temperatures to drop quickly. Rapid development of ice on the bay proceeds from the mouth toward the head of the bay. Any whales present cannot escape to open water and will eventually die or be eaten.
Pond Inlet at the north end of Baffin Island is one such place but Disko Bay in western Greenland is another. In fact, Pond Inlet and Disko Bay are almost identical in geographic layout even though they lie on opposite sides of Baffin Bay, so it’s not surprising that both are locations of repeated entrapment events.
Three highly informative journal articles on the phenomenon of ice entrapment of narwhals and beluga are open access documents that reveal some fascinating details of such incidents, including polar bear predation on trapped whales. h/t T. Nelson Continue reading
Posted in History, Life History, Sea ice habitat, Uncategorized
Tagged Arctic, baffin bay, beluga, climate, climate change, Clint Wright, Disko Bay, entrapment, facts, global warming, narwhal, polar bear, Pond Inlet, predation, prey, risk, sea ice, threatened, trapped, unicorn, Vancouver Aquarium, weather, whales
Here is some old footage shot in 1968-1969 of four Dutch researchers – none of whom had any experience with large carnivores – sent to study polar bears at Kapp Lee on Edgeøya (eastern Svalbard). It’s in Dutch so I don’t know what they’re saying but given the choice of music (Beatles, “All You Need is Love”) I can guess the message.
Still, the images are kind of cool, it’s interesting to see how research was conducted at the time by inexperienced personnel. FYI, I began my university studies in 1968, I was not much younger than these students at the time.
Overwintering Spitsbergen 1968-1969 [Uploaded to youtube 21 October 2012; length 45:55]
Description: In the winter of 1968-1969 stayed four Dutch students on the island Edgeøya east of Spitsbergen to do research as to polar bears. During that expedition, this film made by Paul van de Bosch and Hans Sweet and exhibited by the NOS on Dutch television in 1969.
[Barents Sea polar bear subpopulation background here and here]
I found some additional background that I’ve included below, which shows how naive these young men were, although clearly they had enthusiasm. Dutch researcher Piet Oosterveld was one of the original four on the 1968 expedition and according to a recent news report (see below), will accompany a new expedition to study the effects of global warming. Map below is from the Dutch News story cited below. Spoiler alert: in 1987, Oosterveld was attacked by a polar bear and seriously injured, blamed in part on the rapid increase in polar bear numbers due to their protected status.
Posted in History, Polar bear attacks
Tagged attack, Barents Sea, Dutch researchers, Hacquebord, Norway, Oosterveld, polar bear, Spitsbergen, Svalbard, tagging, video
Have polar bears suffered a contraction of their historical range due to recent declines in summer sea ice? Buried in a recent journal article lies such a claim, one I can’t recall having seen before. That makes it worth close examination.
A drawing of polar bears on St. Matthew Island that accompanied the May 1, 1875 Harper’s Weekly Journal of Civilization article written by Henry Elliot. See here.
The assertion appears in the introduction of a recently published paper that got a lot of attention online (“Implications of the Circumpolar Genetic Structure of Polar Bears for Their Conservation in a Rapidly Warming Arctic” by Peacock and colleagues (2015), discussed previously here, news coverage here and here).
Here is how the authors put it:
“There is already evidence of change in the contemporary distribution of polar bears. For example, polar bears, once common in Newfoundland , are now seen there only infrequently and in small numbers. Similarly, polar bears once regularly summered on St. Lawrence and St. Matthew islands in the Bering Sea [30–32]. Now they are irregularly observed in the Bering Sea and do not spend summers on St. Matthew Island. Although these changes in polar bear distribution may also have been related to overharvest, the recent reductions in the extent of sea-ice due would prevent current and regular use of these areas.” [my emphasis]
There are three main reasons the claim doesn’t hold up to scrutiny:
Posted in History, Sea ice habitat
Tagged climate change, global warming, Gulf of St. Lawrence, Labrador, Little Ice Age, Medieval Warm Period, Newfoundland, range, range contraction, sea ice, St. Lawrence Island, St. Matthew Island, Vibe