Polar bear populations in most of the Canadian Arctic Archipelago (CAA) must be booming, as they are elsewhere. That’s because the ‘experts’ were even more wrong in their predictions of future sea ice conditions than most people realize: they expected the CAA would remain choked with ice during a ‘nearly ice-free’ summer driven by human-caused global warming.
Map presented by Wang and Overland (2012: Fig 3) shows what these experts thought a ‘nearly ice-free’ summer would look like, which they expected to occur by 2030 or so.
Look at the map from Wang and Overland (2012) above, which is what they thought a ‘nearly ice-free’ summer would look like in the year 2030 or so.
Wang and Overland used the same models used by USGS biologists to predict the future survival of polar bears based on habitat loss (Amstrup et al. 2007; Atwood et al. 2016; Durner et al. 2007, 2009). Note the thick ice in the CAA — what USGS experts call the ‘Archipelago’ sea ice ecoregion (denoted by white in the map), indicating ice about 1 metre thick (2-3 feet) — expected to remain at the height of summer in 2030.
[Earlier renditions of sea ice projections (e.g. ACIA 2005) show something similar. The second update of the ACIA released just yesterday (AMAP 2017, described here by the CBC) has prudently included no such firm predictions in their Summary for Policy Makers, just dire warnings of future catastrophe. But see the 2012 update.]
The problem is that ice in this region has been largely absent most summers since 2006, even though overall ice extent has been much more extensive than expected for a ‘nearly ice-free’ summer, as I show below.
This is not another “worse than we thought” moment (Amstrup et al. 2007) — this is sea ice models so wrong as to be useless: failed models used to inform future polar bear survival models that got the bears declared ‘threatened’ with extinction in the US in 2008 (Crockford 2017).
It also means polar bears are almost certainly doing much better than recent population counts indicate, since only one subpopulation out of the six in the CAA has recently been assessed but since polar bear specialists have consistently underestimated the adaptability of this species and the resilience of the Arctic ecosystem to respond to changing conditions, it’s hard to take any of their hyperbole about the future of polar bears seriously. Continue reading
Posted in Conservation Status, Population, Sea ice habitat
Tagged Canadian Arctic Archipelago, Crockford, first year ice, Gulf of Boothia, ice-free, IUCN Polar Bear Specialist Group, IUCN Red List, Kane Basin, Lancaster Sound, multiyear ice, Northwest Passage, PBSG, predictions, sea ice, wrong
Amid reports that ice conditions between Newfoundland and southern Labrador are the worst in living memory, another polar bear was reported ashore in the area — just after biologist Andrew Derocher explained to the CBC that bears only come on land when sea ice conditions “fail.”
“Ice too thick for coast guard’s heavy icebreaker” said a 20 April 2017 CBC report on the state of ice in the Strait of Belle Isle. The pack is thick first year ice (four feet thick or more in places) and embedded with icebergs of much older, thicker ice. The ice packed along the northern shore of Newfoundland is hampering fishermen from getting out to sea and is not expected to clear until mid-May.
NASA Worldview shows the extent of the pack ice over northwest Newfoundland and southern Labrador on 19 April 2017 (the Strait of Belle Isle is the bit between the two):
The same day that the above satellite image was taken (19 April), at the north end of the Strait on the Newfoundland side, a polar bear was spotted in a small community northwest of St. Anthony (marked below, “Wildberry Country Lodge” at Parker’s Brook). It’s on the shore of north-facing Pistolet Bay on the Great Northern Peninsula, near the 1000 year old Viking occupation site of L’Anse aux Meadows.
There were no photos of the Parker’s Brook bear but lots of others have been taken this year of almost a dozen seen along Newfoundland shorelines since early March: see my recently updated post, with an updated map of reported sightings. Harp seals are now abundant in the pack ice of southern Davis Strait, providing polar bears with an ample source of food when they need it most and therefore, a strong attractant to the area.
Yet, as I reported yesterday, polar bear specialist Andrew Derocher told the CBC this week that polar bears are almost always “forced” ashore by poor ice conditions. The CBC report included his tweet from 10 April, where he suggested “failed” Newfoundland ice conditions were the cause of multiple bears onshore in Newfoundland this year.
Similar thick ice conditions off northern Newfoundland (perhaps even worse) occurred in 2007, see Twillingate in the spring of 2007 below:
Yet, in 2007 there was not a single polar bear reported onshore in Newfoundland (as far as I am aware) but this year there were almost a dozen. And the photos taken this year show fat, healthy bears – not animals struggling to survive.
Posted in Polar bear attacks, Sea ice habitat
Tagged Davis Strait, expert, harp seals, Labrador, Newfoundland, onshore, polar bears, population increase, sea ice, sightings
Davis Strait polar bears around Newfoundland and Labrador are currently experiencing what one polar bear specialist refers to as “failed” sea ice conditions, causing bears to come ashore in droves. I’m not making this up.
The ice was so thick in the Strait of Belle Isle between Newfoundland and southern Labrador last week that a ferry was stuck for 24 hours and had to be rescued by an icebreaker.
The boats of fisherman on the north shore of Newfoundland are stuck in thick ice that’s not expected to clear until mid-May at the earliest and they can’t get out to fish.
See this video posted on Twitter two days ago.
The same thing (perhaps even worse) happened in 2007, see Twillingate in the spring of 2007 below:
Yet, in 2007 there was not a single polar bear reported onshore in Newfoundland (as far as I am aware) but this year there were almost a dozen. And the photos show fat, healthy bears – not animals struggling to survive.
According to Andrew Derocher, that’s proof “failed” sea ice is the reason that polar bears came ashore this year but not last year (when there was also lots of ice in late March/early April, see additional maps and graphs below). Last year there were sightings in the middle of winter (January/February) in Labrador and Newfoundland (which I reported here) and one bear was shot in Newfoundland in early May when he advanced on local RCMP officers.
I think Derocher believes he’s set the record straight by offering an interview of his own to refute the things I said to the CBC last week (I talked on two Newfoundland radio stations, which generated a print CBC article). But Newfoundlanders have to deal with used car salesmen just like the everyone else, so I expect they are having a good laugh right now at the expert who’s blaming their polar bear troubles on a lack of sea ice.
A new paper on the evolutionary history of bears (Bears breed across species borders: Kumar et al. 2017) has concluded that hybridization is common and natural among all species of ursids. And while some media outlets (e.g. DailyMail) have framed this as surprisingly convincing proof that experts were wrong to claim that climate change is the cause of recent polar bear X grizzly hybrids, definitive evidence against that interpretation has been available for years to anyone who bothered to look: see my recent “Five facts that challenge hybridization nonsense.”
This genetic evidence is just a cherry on top of the rest but will help get the paper the media attention the authors crave.
Polar bear X grizzly hybrids were known long before climate change and sea ice decline became an issue. See also previous posts here, here, and here. In fact, as I’ve pointed out, “most polar bear hybrids said to exist have not been confirmed by DNA testing” (including virtually all of the bears specialist Andrew Derocher claimed were hybrids, including the latest one from 2016 that prompted such gems as “Love in the time of climate change”).
A polar bear X grizzly hybrid, see Kumar et al. 2017. Photo by A. Derocher.
In my opinion, the most important conclusion of this paper is that occasional but widespread hybridization among bears is why it has been so hard to say with confidence when polar bears arose (which I addressed years ago, in my Polar bear evolution series: Part 1, Part 2, and Part 3). You cannot use traditional methods of pinpointing the timing of speciation events from genetic data if one or more of the species have hybridized (traded genes). See the long, fuzzy “divergence times” for bears in the image below from the Kumar paper.
From Kumar et al. 2017, Fig. 5: “The scale bar shows divergence times in million years and 95% confidence intervals for divergence times [speciation events] are shown as shadings.”
Posted in Evolution, Hybridization
Tagged bears, climate change, evolution, global warming, grolar bear, hybridization, media hype, pizzly, species, ursids
Polar bear numbers have risen since 2005, no matter how you look at it:
USGS estimated 24,500 (average) polar bears in 2005.
IUCN estimated 26,500 (average of 22,000-31,000) in 2015
(assessment completed in July, released in November).
Subpopulation surveys completed or reported after July 2015 (Baffin Bay, Kane Basin, Barents Sea) added ~2,000 bears.
This brings the adjusted average total at 2015 to ~28,500.
Explained in full in this published paper, pgs 20-21:
Crockford, S.J. 2017 V3. Testing the hypothesis that routine sea ice coverage of 3-5 mkm2 results in a greater than 30% decline in population size of polar bears (Ursus maritimus). PeerJ Preprints 2 March 2017. Doi: 10.7287/peerj.preprints.2737v3 Open access. https://doi.org/10.7287/peerj.preprints.2737v3
Apparently, some locals were upset that a polar bear that refused to be scared away from a Newfoundland community over the weekend was shot as it advanced on conservation officers and a crowd of onlookers who refused to disperse (see updated report here on recent Newfoundland polar bear sightings, with annotated map).
“Polar bear shot by wildlife officers near Catalina after being deemed public safety risk” (CBC 10 April 2017)
What these animal lovers may not realize is that Newfoundland in March and April is not a Churchill-like situation: polar bears are in strong hunting mode right now.
Polar bears in late winter and spring have an immense drive to kill and eat as much as possible. Even bears that look well fed will continue to kill and eat. Enticing smells attract them onshore as they investigate any food possibility (see list below).
Seriously, you don’t want that food possibility to be you.
Polar bears can go from watching to charging, in the blink of an eye. You can’t outrun one. Killing quickly is what they do and they are immensely strong. Polar bears generally go for a killing bite to the head. Things to think about when a polar bear is prowling your community…
Posted in Advocacy, Polar bear attacks, Uncategorized
Tagged attacks, attractants, defense kills, hunting, Newfoundland, onshore, polar bear, sightings, spring, winter
Without a shred of evidence, Canada’s Maclean’s magazine claims recent polar bear sightings in Newfoundland and Labrador are due to global warming — and concludes that such incidents are bound to get worse.
But since it’s likely that polar bear populations in Davis Strait are still increasing (as they were in 2007), Maclean’s might be correct in their prophesy that bear visitations are bound to get worse — just not for the reason they think.
Without any justification or even a quote from an expert, the author of this piece (Meagan Campbell) blames man-made global warming for recent polar bear visits to Labrador and Newfoundland:
“Since bear sightings in the early winter have been linked to climate change, some parents are more concerned for their future grandchildren.”
That’s just bad logic. Actually, the fact that global warming has not killed off polar bears as predicted means there are lots of bears to come ashore causing problems in late winter (while they wait for Arctic seal pups to be born, so they can eat them).