Svalbard is still ice-free this fall, which it has been rather consistently for at least ten years but the amount of sea ice greater than ‘normal’ in the Eastern Canadian Arctic at this date is something to behold. Yet contrary to predictions, polar bears in Svalbard are thriving.
Comments Off on Eastern Canadian Arctic has much more sea ice than usual while Svalbard polar bears deal with less
Posted in Life History, Sea ice habitat
Tagged baffin bay, Barents Sea, Davis Strait, Franz Josef Land, freeze-up, Hudson Bay, polar bear, sea ice, Svalbard, western hudson bay
In an article published last week, polar bear specialist Jon Aars is quoted as saying that Svalbard bears are “unexpectedly” thriving. However, he fails short of admitting that the bears don’t really need summer ice as long as they are well-fed in spring, which they have been for the last two decades—this year included.
Aars said the sea ice in this area is declining more than twice as fast as anywhere else in the Arctic. But the polar bears here — unexpectedly — are thriving. [E. Haavik, Svalbard’s polar bears persist as sea ice melts — but not forever, 21 July 2022; my bold]
The suggestion by Aars that the Svalbard archipelago could one day be ice-free for the entire year is speculative hyperbole but even if that were to happen, it would only mean the permanent movement of 300 or so Svalbard bears to Franz Josef Land (still within the Barents Sea) where ice conditions are less volatile.
Continue readingComments Off on Expert admits polar bears in Svalbard are thriving despite the greatest loss of sea ice in the Arctic
Posted in Conservation Status, Life History, Population, Sea ice habitat
Tagged Barents Sea, Franz Josef Land, persistent, polar bear, sea ice, Svalbard, thriving
Sea ice around Svalbard, Norway at the end of February 2020 is way above average, as the graph below shows – with more polar bear habitat now than there has been in two decades.
Some comparison charts below show that the graph above includes some very high ice years in the 1980s (reaching that dotted line above the mean) for which only global charts are available.
However, contrary to suggestions that more Svalbard ice is better for polar bears, there is no evidence that low extent of sea ice habitat in winter or summer over the last two decades harmed polar bear health, reproductive performance, or abundance. In fact, polar bear numbers in 2015 were 42% higher than they were in 2004 (although not a significant increase, statistically speaking) and most bears were found to be in excellent condition.
This suggests a return to more extensive ice to the Svalbard region in winter will have little impact on the health of the entire Barents Sea subpopulation, although it might change where pregnant females are able to make their maternity dens if ice forms early enough in the fall. In other words, the population should continue to grow as it has been doing since the bears were protected by international treaty in 1973.
UPDATE 3 March 2020: According to 28 February tweet by the Norwegian Ice Service, which I just saw today, “the last time there was this much sea ice around Svalbard on this day of the year [28 February] was 2004“. Somehow, I missed 2004 when I was looking through the archive, so I have modified the text below accordingly; see the 2004 chart below and here.
Comments Off on Svalbard Norway now has more polar bear habitat than it did two decades ago
Posted in Life History, Population, Sea ice habitat
Tagged Barents Sea, body condition, cub survival, denning, facts, Franz Josef Land, polar bear, science, sea ice, Svalbard
Word that Russia is planning to generate a count of polar bears along its entire Arctic coast within the next few years is good news indeed, as it will resolve a long-standing gap in population estimates that have not been dealt with at all well by the polar bear community. Whether North American and European academics will accept the results of the aerial surveys is another matter entirely, especially if the numbers are higher than they like, which is what happened with the first Russian Kara Sea count in 2013.
Up first will be the Chukchi and East Siberian Seas in 2021, the Laptev and Kara Seas, in 2022, and the eastern Barents Sea around Franz Josef Land in 2023.
Comments Off on First-ever polar bear population survey for entire Russian coast planned for 2021-2023
Posted in Population
Tagged Barents Sea, Chuckhi Sea, counts, Franz Josef Land, global estimate, IUCN Red List, Kara Sea, Laptev Sea, PBSG, polar bear, population size, Russian
In late June, one of the most powerful icebreakers in the world encountered such extraordinarily thick ice on-route to the North Pole (with a polar bear specialist and deep-pocketed, Attenborough-class tourists onboard) that it took a day and a half longer than expected to get there. A few weeks later, in mid-July, a Norwegian icebreaker also bound for the North Pole (with scientific researchers on board) was forced to turn back north of Svalbard when it unexpectedly encountered impenetrable pack ice.
A polar bear on hummocked sea ice in Franz Josef Land. Photo by Michael Hambrey, date not specified but estimated based on tour dates to be 22 or 23 June 2019.
Apparently, the ice charts the Norwegian captain consulted showed ‘first year ice‘ – ice that formed the previous fall, defined as less than 2 m thick (6.6 ft) – which is often much broken up by early summer. However, what he and his Russian colleague came up against was consolidated first year pack ice up to 3 m thick (about 10 ft). Such thick first year ice was not just unexpected but by definition, should have been impossible.
Ice charts for the last few years that estimate actual ice thickness (rather than age) show ice >2 m thick east and/or just north of Svalbard and around the North Poie is not unusual at this time of year. This suggests that the propensity of navigational charts to use ice ‘age’ (e.g. first year vs. multi-year) to describe ice conditions could explain the Norwegian captain getting caught off-guard by exceptionally thick first year ice. It also provides an explanation for why the polar bear specialist onboard the Russian icebreaker later failed to explain that first year ice of such shocking thickness was truly extraordinary, not just a bit thicker than usual.
Comments Off on Shockingly thick first year ice between Barents Sea and the North Pole in mid-July
Posted in Advocacy, Sea ice habitat
Tagged Barents Sea, extent, first year ice, Franz Josef Land, ice age, icebreaker, North Pole, polar bear, sea ice, Svalbard, thick ice, thin ice
January is the first month of the Arctic winter, the season when most polar bears really struggle to find enough to eat.
Here is what the sea ice looked like around the Arctic at the end of this month.
Compare to last year:
Comments Off on Abundant polar bear habitat across the Arctic at the start of winter
Posted in Advocacy, Conservation Status, Life History, Sea ice habitat
Tagged Arctic, Barents Sea, Canada, denning, Derocher, East Coast, Franz Josef Land, polar bear, sea ice, Svalbard, winter
Last week, the Norwegian Polar Institute updated their online data collected for the Svalbard area to include 2017 and 2018 — fall sea ice data and spring polar bear data. Older data for comparison go back to 1993 for polar bears and 1979 for sea ice, showing little to no impact of the reduced ice present since 2016 in late spring through fall.
Here’s what the introduction says, in part [my bold]:
“…The polar bear habitat is changing rapidly, and the Polar Basin could be ice-free in summer within a few years. Gaining access to preferred denning areas and their favourite prey, ringed seals, depends on good sea ice conditions at the right time and place. The population probably increased considerably during the years after hunting was banned in 1973, and new knowledge indicates that the population hasn’t been reduced the last 10-15 years, in spite of a large reduction in available sea ice in the same period.”
See Aars et al. 2017 for details on the 2015 Svalbard polar bear population count, keeping in mind that the subpopulation region is called “Barents Sea” for a reason: only a few hundred individuals currently stick close to Svalbard year round while most Barents Sea bears inhabit the pack ice around Franz Josef Land to the east (Aars et al. 2009; Crockford 2017, 2018).
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Comments Off on Svalbard polar bear data 2016 through 2018 shows no impact of low ice years
Posted in Advocacy, Conservation Status, Sea ice habitat
Tagged Barents Sea, body condition, decline, denning, Derocher, Franz Josef Land, litter size, mothers with cubs, polar bear, population, sea ice, Svalbard
Svalbard in the western Barents Sea has recently had less sea ice extent than it had in the 1980s, especially in the west and north, but this is not unprecedented.
New evidence from clams and mussels with temperature-sensitive habitat requirements confirm that warmer temperatures and less sea ice than today existed during the early Holocene period about 10.2–9.2 thousand years ago and between 8.2 and 6.0 thousand years ago (based on radio carbon dates) around Svalbard. Barents Sea polar bears almost certainly survived those previous low-ice periods, as they are doing today, by staying close to the Franz Josef Land Archipelago in the eastern half of the region where sea ice is more persistent.
As this sea ice chart for 18 April 2018 shows, ice this month has been virtually absent from the west and north coasts of the Svalbard Archipelago, while Franz Josef Land to the east is surrounded by highly concentrated pack and land-fast ice.
From a new paper by Jan Mangerud and John Svendsen (2018) [my bold]:
Svalbard, located between 74° and 81°N, is the warmest place on Earth at this latitude (Drange et al., 2013). This is because of the North Atlantic Current and large-scale atmospheric circulation which transport warm water and air masses from lower latitudes northwards across the Atlantic and along the coast of Norway to Svalbard (Figure 1). Yet, during the Holocene Thermal Maximum, the climate of Svalbard was considerably warmer than at present.
The transition from Younger Dryas cold to Holocene Thermal Maximum warm conditions took place very rapidly, according to records from nearby Greenland (Taylor et al. 1997), warming in “steps” of about five years each over a period of about 40 years. This was at least as fast, if not faster than, recent Arctic warming between the 1980s and 2015. And since polar bears of the Barents Sea and adjacent Arctic areas appear to have survived this change to Holocence Thermal Maximum conditions, it challenges the notion that recent warming has been (or will be) too fast to allow polar bears to survive without huge changes in their present distribution (Amstrup et al. 2007).
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Comments Off on Less Svalbard polar bear habitat during the early Holocene than now
Posted in Conservation Status, Sea ice habitat
Tagged Amstrup, Barents Sea, Franz Josef Land, Holocene, Holocene Thermal Maximum, Norway, polar bears, Russia, Svalbard
Consensus polar bear expert Andrew Derocher has been busy over the last few weeks, expounding a story of doom regarding Svalbard area polar bears (e.g. here and here), ridiculing the suggestion that Franz Josef Land is viable alternate habitat for Barents Sea bears, especially pregnant females looking for a place to den and give birth. But the facts say otherwise.
Below are the long answers, with references and ice maps, to the questions Derocher asked in his 21 December 2017 tweet (above), a refreshing change from the ‘take my word for it, I’m the official expert’ answer one gets from him, along with derogatory slurs directed at those who don’t share his pessimism.
UPDATED 1 February 2019. Two references added.
Comments Off on Franz Josef Land is a sea ice refugium for most pregnant Barents Sea polar bears
Posted in Life History, Population, Sea ice habitat
Tagged abundance, Arctic islands, Barents Sea, den habitat, estimates, Franz Josef Land, Norway, polar bears, pregnant, Russia, sea ice, Svalbard
Sea ice development in eastern Svalbard this fall is lagging well behind the rest of the Arctic. Several polar bear researchers (e.g., Andrew Derocher here and here) have recently been raising the alarm that this might be devastating for Barents Sea females looking for suitable denning sites.
The implication is that pregnant polar bear females are inflexible – so fixated on one location to give birth that they are unable or unwilling to choose an alternative if conditions preclude using their preferred location this year. However, the available facts do not support such a pessimistic attitude.
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Comments Off on Barents Sea polar bears adapt to changing sea ice conditions
Posted in Life History, Sea ice habitat
Tagged Aars, Barents Sea, dens, Derocher, flexibility, Franz Josef Land, Hopen Island, Kong Karls Land, nearshore, pelagic, philopatry, polar bear, polar bear facts, pregnant females, sea ice, Svalbard
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