Posted onDecember 3, 2015|Comments Off on Spring sea ice prediction for next year off Newfoundland: extensive ice coverage
EATEN – my new polar bear attack novel – is set in Newfoundland 2025 for a reason. I wondered: what if sea ice coverage 10 years from now is as high or higher than it has been for the last two years, with inevitable positive effects on Davis Strait harp seal and polar bear populations?
The Canadian Ice Service prediction for this region, released earlier this week (1 December 2015, see references for link), is that 2016 is set to meet my “what-if” scenario handily. Nine years to go! See the CIS expected ice coverage for 19 February 2016 below (CIS fig. 3):
How does the above ice map compare to the last two years? At least as high or higher. Have a look below.
This is a previously unpublished summary, written exclusively for The Arctic Journal, of my peer-reviewed, fully referenced essay on this topic that was published earlier this year by the Global Warming Policy Foundation in their “Briefing Paper” series (#16, June 8, 2015: The Arctic Fallacy: Sea Ice Stability and the Polar Bear), which includes a foreword by Dr. Matthew Cronin, Professor of Animal Genetics at the University of Alaska Fairbanks. Pdf here.
Posted onAugust 6, 2015|Comments Off on Pacific walrus sob stories begin again
Now we have poor hunting conditions in the Bering Strait touted as evidence that “walrus migration patterns have changed” with the implication that this is because “…the past eight years have had the eight lowest amounts of summer sea ice on record” due to man-made global warming.
A subsistence lifestyle is hard, particularly so if it depends on a highly mobile, migratory herd animal. Think Barren-ground Inuit caribou hunters, who often starved because herd sizes declined for a few years or moved unpredictably.
Many factors – seasonal weather, last year’s winter conditions, size of the herd, food supply – all affect where and when a migratory herd will move and the likelihood it will be positioned for optimal harvesting by hunters. Add another highly variable factor into that – Bering Sea ice – and you have a highly unpredictable food supply, especially if you sit in one spot (like on St. Lawrence Island) and expect that migratory herd animal to come within reach.
Hunting walrus from St. Lawrence Island depends on just the right combination of ice and winds. Too much ice is not good, too much open water is not good, and too much wind is not good.
Alaska Dispatch, courtesy the Associated Press, reports St. Lawrence natives are again short of walrus meat because of “warm temperatures”: “Warming temps push walrus north, leaving Alaska villages without traditional food source”(Rachel D’Oro, The Associated Press, August 6, 2015). And the caption of the above USGS (A. Sonsthagen) photo predictably implies all current hunting troubles can be blamed on climate channge:
“The walruses in this July 2012 file photo are hauled out in the Eastern Chukchi Sea. Walrus migration patterns have changed as sea ice and other environmental factors have shifted — and that’s spelled trouble for Alaska Native communities who hunt them for subsistence.”
The people of St. Lawrence Island and the Bering Strait that depend on walrus for subsistence have my sympathy, they indeed have a hard life – but this is not a tale of woe about the status of Pacific walrus and changing summer sea ice.
Bering Strait natives hunt walrus in spring, from mid-April to early June (Huntington et al. 2013). All indications are that walrus are moving differently than they used to in summer because the population is now very large. As far as I know, there is no new population information on walrus that wasn’t available last year, when I covered this topic extensively (Crockford 2014; video below).
Posted onJune 25, 2015|Comments Off on Polar bear habitat update: many bears on the ice in Hudson Bay, lots of sea ice globally
Polar bear habitat over Hudson Bay was average this week (at 60% coverage), despite the odd pattern of breakup – but the end of spring in the Arctic is only 5 days away and there is still plenty of polar bear habitat in all regions.
According to the Canadian Ice Service (CIS), there is still more ice in the eastern portion of the bay than usual and much less in the northwest (Fig. 1 below). There is far more ice than average ice in Hudson Strait, the approach to southern Davis Strait.
Figure 1. Hudson Bay sea ice, difference from average at 22 June 2015. Blue is less than average, red is more than average. CIS. Click to enlarge.
Posted onJune 24, 2015|Comments Off on Many polar bears cubs seen in Svalbard this year, says Norwegian biologist
Good news from Norway: polar bears around Svalbard are in excellent condition this spring and many females with new cubs have been spotted. This is a marked turn around from conditions just last year.
According to a Norwegian news outlet yesterday, Jon Aars (Fig. 1, below), from the Norwegian Polar Institute, confirms that this has been an excellent year for polar bear cubs around Svalbard because there has been abundant sea ice near denning areas on the east coast.
Posted onMay 21, 2015|Comments Off on Arctic polynyas and sea ice extent in Canada at 20 May 2015
The map of sea ice extent in Canada at 20 May 2015 is an almost-perfect example of the placement of recurring patches of open water polynyas that were present in the Canadian Arctic at this time of year in 1975-1979. Notes from field work on shore leads in Hudson Bay ice at May, 1948 offer further insight into the current pattern of sea ice cover on the bay.
May is traditionally the time when recurring polynyas in the Canadian Arctic become more prominent and persistent shore leads (cracks in the ice near shore, also called “flaw leads”) become wider. Polar bears hunt around these polynyas because ringed and bearded seals congregate around them in the spring (Stirling et al. 1981; Stirling 1997). These polynyas are often not truly “open water” but covered by thin ice that’s easy for seals to break through.
Slight differences in location and size of polynyas and shore leads from year to year (especially in spring) are governed primarily by prevailing winds (Dunbar 1981:29) and to a lesser extent, currents. See my previous discussion on Beaufort Sea polynyas, with references: Beaufort Sea polynyas open two weeks before 1975 – open water is good news for polar bears.
This suggests that while sea ice cover over Hudson Bay and the Beaufort Sea is now a bit below average for this time of year (as the maps for this week show), it does not necessarily portend an earlier breakup or longer open-water period later in the year.
Posted onMay 18, 2015|Comments Off on Polar bear habitat update: Hudson Bay sea ice breakup on track
Hudson Bay sea ice coverage is only slightly below average for this time of year (week of 14 May, below) but well above levels for 2006, when Western Hudson Bay breakup was relatively early).
Figure 1. Sea ice coverage over Hudson Bay for the week of 14 May, 1971-2015. Canadian Ice Service. Click to enlarge.
Even at its highest extent in April, Hudson Bay is only 97-98% ice covered (due to persistent shoreleads and polynyas), which means ice levels are currently only 10% or so below maximum. In other words, there is still lots of polar bear hunting habitat over the bay.
That’s a bit lower than ice coverage was for the last two years at this date (2013-2014), which had average or above average ice cover. However, there is currently a bit more ice on Hudson Bay than there was in 2011 and 2012 – and much more than there was in 2010 and 2006. Continue reading
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Posted onMay 15, 2015|Comments Off on Beaufort Sea polynyas open two weeks before 1975 – open water is good news for polar bears
With masses of very thick, multiyear ice off Alaska this spring, the developing polynyas(open water) at either end of the Beaufort Sea are providing essential polar bear hunting habitat.
Patches of open water in the Beaufort Sea are naturally recurring phenomena. This year we have two excellent examples, shown by the yellow arrows in the sea ice thickness map above (from the Naval Research Laboratory).
The eastern-most polynya forms in the Canadian portion of the Beaufort most years in the spring. This open water feature is so common it has a name – the Cape Bathurst polynya. Last year, there wasn’t an obvious polynya there until sometime in June, but in 1975, a patch of open water almost as large (or larger) as this year’s had developed by the end of May (Fig. 1).
Figure 1. Cape Bathurst polynya at 28 May 1975 (Smith and Rigby 1981:Fig. 14h) and the polynya this year at 14 May (Canadian Ice Service). See discussion in the text below about the relative sizes. Click to enlarge.
In fact, the Cape Bathurst polynya is a critical place for ringed seals and bearded seals to congregate in spring. Therefore, this is where many Southern Beaufort polar bears go to hunt. The presence of the polynya is especially crucial in years like this one, when very thick sea ice covers most of the Beaufort Sea. Continue reading
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Posted onMay 14, 2015|Comments Off on Snow depth over spring sea ice affects polar bear feeding success and ringed seal survival
Snow depth over sea ice in spring affects the hunting success of polar bears on ringed seal (Phoca hispida) pups, but the relationship is more complicated than you might think and there is less data on this phenomenon than you would believe.
This year, it was very cold in Eastern North America, with record-breaking snow fall in some areas. Snow depth was apparently greater than average over Hudson Bay sea ice this spring but was it deep enough to have impaired polar bear hunting success?
Posted onApril 29, 2015|Comments Off on Polar bear season for Newfoundland residents still going strong, recent sightings confirm
Two recent sightings of polar bears along the north shore of Newfoundland are a reminder that sea ice is still a prominent feature of the Davis Strait polar bear subpopulation landscape at this time of year.
A polar bear was sighted in the community of La Scie, northern Newfoundland Monday, 27 April (pictured above, swimming in the harbour), while another landed in the town of Fogo, on Fogo Island, last week (see maps below). Continue reading
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Watch polar bear habitat reform in the Canadian Arctic: “last 10 days” Canadian Ice Service animation (works anytime) HERE.
See Quote archive for details.
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