A Geological Perspective of Polar Bears

Guest “geological perspective” by David Middleton

A Popular Narrative

Polar bears (Ursus maritimus) are the poster child for the impacts of climate change on species, and justifiably so. To date, global warming has been most pronounced in the Arctic, and this trend is projected to continue. There are suggestions that before mid-century we could have a nearly ice-free Arctic in the summer. This increases the urgency with which we must act to reduce our greenhouse gas emissions to delay or avoid some of the worst consequences of climate change.

WWF
Figure 1. Change.org

A Geological Perspective

Figure 2. “Global polar bear population size estimates to 2018. From Chapter 10 of The Polar Bear Catastrophe That Never Happened (Crockford 2019).” Polar Bear Science.

Effects of declining ice on polar bear behavior and habitat selection

Among all polar bear subpopulations, those occurring in the Beaufort and the Chukchi seas have experienced some of the greatest losses of sea ice in the entire Arctic Ocean. The mechanisms that link habitat to population trend, however, have not been quantitatively described. The role of habitat preference on behavior (i.e., movement and activity) or whether some habitats are important for life history requirements is uncertain. Movements of polar bears are linked to foraging success and energetic costs. Hence, movements, as a proxy for behavior and energetics, may be indicative of habitat value and provide a quantifiable means to elucidate mechanisms of polar bear population response to a changing Arctic. We are using polar bear location data collected by the USGS since 1985 to develop models of polar bear distribution that account for long-term changes in behavior and habitat function. This research will provide products that can be used by managers to mitigate adverse impacts to polar bears and polar bear habitats from anthropogenic activities.

USGS

Key passage:

Among all polar bear subpopulations, those occurring in the Beaufort and the Chukchi seas have experienced some of the greatest losses of sea ice in the entire Arctic Ocean. The mechanisms that link habitat to population trend, however, have not been quantitatively described. The role of habitat preference on behavior (i.e., movement and activity) or whether some habitats are important for life history requirements is uncertain.

USGS

“The mechanisms that link habitat to population trend” cannot be “quantitatively described.”

November 14, 2018
First tally of U.S.-Russia polar bears finds a healthy population
Hannah Hickey
UW News

Not all polar bears are in the same dire situation due to retreating sea ice, at least not right now. Off the western coast of Alaska, the Chukchi Sea is rich in marine life, but the number of polar bears in the area had never been counted. The first formal study of this population suggests that it’s been healthy and relatively abundant in recent years, numbering about 3,000 animals.

The study by researchers at the University of Washington and federal agencies is published Nov. 14 in Scientific Reports, an open-access journal from the Nature Publishing Group.

“This work represents a decade of research that gives us a first estimate of the abundance and status of the Chukchi Sea subpopulation,” said first author Eric Regehr, a researcher with the UW’s Polar Science Center who started the project as a biologist in Alaska with the U.S. Fish and Wildlife Service. “Despite having about one month less time on preferred sea ice habitats to hunt compared with 25 years ago, we found that the Chukchi Sea subpopulation was doing well from 2008 to 2016.

[…]

Of the world’s 19 subpopulations of polar bears, the U.S. shares two with neighboring countries. The other U.S. subpopulation — the southern Beaufort Sea polar bears, whose territory overlaps with Canada — is showing signs of stress.

“The southern Beaufort Sea subpopulation is well-studied, and a growing body of evidence suggests it’s doing poorly due to sea-ice loss,” Regehr said.

[…]

Recent ecological observations had suggested that Chukchi Sea bears are doing well. A study led by co-author Karyn Rode, at the U.S. Geological Survey, showed the top predators have similar amounts of body fat as 25 years ago, a good indicator of their overall health.

The current study is the first assessment of the subpopulation size using modern methods. It estimates just under 3,000 animals, with generally good reproductive rates and cub survival.

[…]

For the first time, the model also considered local and traditional ecological knowledge collected by the North Slope Borough of Alaska from Native hunters and community members who have generations of experience with polar bears.

“It was important to bring our science together with the observations and expertise of people who live in polar bear country year-round and understand the animals in different ways,” Regehr said.

University of Washington

If the loss of sea ice due to global warming is stressing out the Beaufort Sea polar bears, why are they doing so well in the Chukchi Sea?

The Chukchi Sea is more ice-free than the Beaufort Sea…

Figure 3. Arctic sea ice. NASA
Figure 4. Arctic sea ice extent. NASA

The “core study area” was the between Lisburne and Seward Peninsulas…

Figure 5. “The striped area on the left shows the Chukchi Sea polar bear subpopulation’s range. Sea ice reaches south to the dotted line in winter, and retreats to the solid black line in summer. The right shows a closeup of the study area off Alaska’s coast. White circles show where polar bears were tagged between 2008 and 2016.Regehr et al./Scientific Reports” (UW)

The “core study area” has been especially hard-hit by sea ice loss…

Figure 6. June 1979
Figure 7. June 2019
Figure 8. Animation

Setting aside the fact that overall polar bear populations don’t seem to be declining, how did polar bears manage to survive the vast majority of the Holocene Epoch, when sea ice was far less extensive than today? For that matter, how did they survive the Eemian (Sangamonian) interglacial stage, when the Arctic was 5-10 °C warmer than it is today?

The Holocene Epoch

The Chukchi Sea, the place where the polar bear population appears stable and healthy was nearly ice-free for much of the Holocene.

Figure 9. “Modern sea-ice cover in the study area, expressed here as the number of months/year with >50% coverage, averages 10.6 ±1.2 months/year… Present day SST and SSS in August are 1.1 ± 2.4 8C and 28.5 ±1.3, respectively… In the Holocene record of core HLY0501-05, sea-ice cover has ranged between 5.5 and 9 months/year, summer SSS has varied between 22 and 30, and summer SST has ranged from 3 to 7.5 8C (Fig. 7). (McKay et al., 2008)

Over most of the Holocene, >50% sea ice coverage occurred from 5.5 to 9 months each year.  During the “Anthropocene”, >50% sea ice coverage has ranged from 9 to 12 months each year.

Figure 10. How did the polar bears survive with so little sea ice?

Stein et al., 2017 (H/T tty) provides a great description of a rather novel method of determining paleo sea ice extent.

In a pioneering study by Belt et al. (2007), the ability to (semi-)quantitatively reconstruct paleo-sea ice distributions has been significantly improved by a biomarker approach based on determination of a highly branched isoprenoid (HBI) with 25 carbons (C25 HBI monoene = IP25). This biomarker is only biosynthesized by specific diatoms living within the Arctic sea ice (Brown et al., 2014) and appears to be a specific, sensitive and stable proxy for Arctic sea ice in sedimentary sections representing Late Miocene to Recent times (Stein et al., 2012, 2016; Belt and Müller, 2013; Stein and Fahl, 2013; Knies et al., 2014). The presence of IP25 in the studied sediments is direct evidence for the presence of sea ice.

[…]

For more semi-quantitative estimates of present and past sea ice coverage, M€uller et al. (2011) combined the sea-ice proxy IP25 and phytoplankton biomarkers in a phytoplankton- IP25 index, the so-called ‘PIP25 index’:

PIP25 = [IP25]/([IP25] + ([phytoplankton marker] x c))

with c is the mean IP25 concentration/mean phytoplankton biomarker concentration for a specific data set or core.

Stein et al., 2017

This schematic diagram from Belt et al., 2013 relates the PIP25 index to sea ice conditions:

Figure 11. Relationship of sea ice conditions to PIP25 index (Belt ea al., 2013). Click to enlarge.

Generally speaking, the PIP25 index correlates to sea ice extent as follows:

  • >0.7 = Extended, perennial (year-round) ice cover
  • 0.5-0.7 = Seasonal ice cover/ice edge situation
  • 0.1-0.3 = Reduced ice cover
  • <0.1 = Ice-free year-round

Stein et al. 2017, constructed a cross-section of PIP25 curves across the Arctic from the Fram Strait to the Chukchi Sea.

Figure 12. Location map of sediment cores and cross-section A-A’. (modified after Stein et al., 2017)

All four core locations currently reflect seasonal ice cover/ice edge situations (PIP25 index 0.5-0.7), with the Fram Strait being an ice edge situation and the other three reflecting seasonal ice cover.

Figure 13. Cross-section A-A’. High and low refer to Northern Hemisphere insolation.

Three key takeaways:

  1. Maximum Holocene sea ice extent occurred within the past 500-1,000 years at every location.
  2. The current sea ice extent is higher at all of the locations than over 50% to 85% of the Holocene.
  3. Polar bears survived low sea ice extent over most of the Holocene.

When I plot the cross-section on Kinnard’s probability map, we can see that the entire area of low ice extent larger than present day, has been seasonal throughout most of the Holocene.

Figure 14. Probability of sea ice occurrence (1870-2003) A = maximum, B= minimum. (Kinnard et al., 2008)

A significant reduction in Arctic summer sea ice relative to today, would be returning to Early Holocene conditions. If we currently have an “Anthropocene in the Arctic,” it’s actually icier than most of the Holocene’s “Goldilocks conditions.”

When did polar bears first evolve?

No one really knows for sure.

Polar Bear Evolution Was Fast and Furious

By Elizabeth Pennisi May. 8, 2014 , 12:00 PM

For polar bears, being tubby is a way of life. Fat can make up 50% of their body weight; the blubber-laden seals they eat make bacon look downright healthy. Now, a new, extensive comparison of the genomes of polar bears and their closest relative, the brown bear, has revealed how polar bears survive such unhealthy diets.

The work also suggests that the bears evolved these changes relatively quickly, likely because they had to adapt to extreme conditions that forced them to switch to a diet that would be toxic to other mammals. “It’s a schoolbook example of evolution,” says Eske Willerslev, an evolutionary geneticist at the University of Copenhagen who helped the lead the research.

Brown bears—some of which are called grizzlies—and polar bears are closely related and are even able to interbreed. In the past few years, researchers have used genetic information to sort out this relationship and to understand how polar bears thrive in the frigid Arctic, feeding primarily on seals and other marine life captured from holes in the ice. This work has included sequencing the animals’ genomes, which has indicated that polar bears are truly a distinct species that at times lived apart from brown bears and at times intermingled and interbred with them. But researchers disagree about when the polar bear began to split off from brown bears, with estimates ranging from about 600,000 years to as much as 5 million years ago.

In the latest sequencing effort, Willerslev and researchers from Denmark, China, and the United States analyzed the genomes of 80 polar bears from Greenland and 10 brown bears from North America and Europe. “[It’s] the most comprehensive genomic data set to date, as far as bears are concerned,” says Frank Hailer, an evolutionary biologist from Goethe University Frankfurt in Germany.

Drawing on that data, Willerslev and his colleagues conclude that polar bears split off from brown bears between 343,000 and 479,000 years ago. Although little more than a blink in time from an evolutionary perspective, that was long enough for key genetic differences to evolve, they note in a report today in Cell.

[…]

Science

Estimates have ranged from 70,000 to 5,000,000 years ago. The oldest confirmed polar bear fossil dates to 110,000 to 130,000 years ago… Meaning that polar bears survived the Eemian interglacial stage.

The peak warmth of the Eemian interglacial stage marks the boundary between the Late Pleistocene Tarantian Age and the Middle Pleistocene Ionian Age.

Figure 15. Pleistocene stratigraphic nomenclature, SQS.
Figure 16. “The oxygen isotopes in the ice imply that climate was stable during the last interglacial period, with temperatures 5 °C warmer than today.” North Greenland Ice Core Project members, 2004

If sea ice is so crucial to polar bear survival, how did they survive the Eemian? Well it appears that despite this:

The last time that Arctic temperatures were significantly higher than today was the Early Holocene Thermal Maximum910. The Holocene, however, is an interglacial cycle not concluded yet. This certainly justifies climatic evaluations of older, concluded warm interglacial cycles such as the last interglacial (LIG), i.e., Marine Isotope Stage (MIS) 5e (Eemian), lasting from about 130 to 115 ka and often proposed as a possible analog for our near-future climatic conditions on Earth1112. Based on proxy records from ice, terrestrial and marine archives, the LIG is characterized by an atmospheric CO2 concentration of about 290 ppm, i.e., similar to the pre-industrial (PI) value13, mean air temperatures in Northeast Siberia that were about 9 °C higher than today14, air temperatures above the Greenland NEEM ice core site of about 8 ± 4 °C above the mean of the past millennium15, North Atlantic sea-surface temperatures of about 2 °C higher than the modern (PI) temperatures1216, and a global sea level 5–9 m above the present sea level17. In the Nordic Seas, on the other hand, the Eemian might have been cooler than the Holocene due to a reduction in the northward flow of Atlantic surface water towards Fram Strait and the Arctic Ocean, indicating the complexity of the interglacial climate system and its evolution in the northern high latitudes121819.

Stein et al., 2017

Arctic sea ice didn’t totally vanish…

Figure 17. “Simulation of Arctic sea ice cover of the Last Interglacial and the pre-industrial climate. Last Interglacial (LIG) conditions were simulated for three time slices: LIG-130 (130 ka), LIG-125 (125 ka), and LIG-120 (120 ka). White circles indicate locations of the four studied sediment cores. ” Stein et al., 2017
Figure 18. Too fracking funny!

References

Belt S.T., Müller J.  “The Arctic sea ice biomarker IP25: A review of current understanding, recommendations for future research and applications in palaeo sea ice reconstructions”. (2013)  Quaternary Science Reviews,  79 , pp. 9-25. Belt_2013

Crockford, Susan J, and Global Warming Policy Foundation. The Polar Bear Catastrophe That Never Happened. London, The Global Warming Policy Foundation, 2019.

Fetterer, F., K. Knowles, W. N. Meier, M. Savoie, and A. K. Windnagel. 2017, updated daily. Sea Ice Index, Version 3. [Sea Ice Monthly By Year]. Boulder, Colorado USA. NSIDC: National Snow and Ice Data Center. doi: https://doi.org/10.7265/N5K072F8. [Accessed October 16, 2019].

Kinnard, C., Zdanowicz,C.M., Koerner,R .,Fisher,D.A., 2008. “A changing Arctic seasonal ice zone–observations from 1870–2003 and possible oceanographic consequences”. 35, L02507. Kinnard_2008

McKay, J.L., A. de Vernal, C. Hillaire-Marcel, C. Not, L. Polyak, and D. Darby. 2008. Holocene fluctuations in Arctic sea-ice cover: dinocyst-based reconstructions for the eastern Chukchi Sea. Can. J. Earth Sci. 45: 1377–1397

Middleton, David. “Back to the Anthropocene! Arctic Sea Ice Edition.” Watts Up With That?, 17 Oct. 2019, wattsupwiththat.com/2019/10/17/back-to-the-anthropocene-arctic-sea-ice-edition/.

North Greenland Ice Core Project members. 2004. “High-resolution record of Northern Hemisphere climate extending into the last interglacial period”. Nature 431(7005):147-151.

Stein, R., Fahl, K., Gierz, P. et al. Arctic Ocean sea ice cover during the penultimate glacial and the last interglacial. Nat Commun 8, 373 (2017). https://doi.org/10.1038/s41467-017-00552-1

Stein, R. , Fahl, K. , Schade, I. , Manerung, A. , Wassmuth, S. , Niessen, F. and Nam, S. (2017), Holocene variability in sea ice cover, primary production, and Pacific‐Water inflow and climate change in the Chukchi and East Siberian Seas (Arctic Ocean). J. Quaternary Sci., 32: 362-379. doi:10.1002/jqs.2929 stein2017

72 thoughts on “A Geological Perspective of Polar Bears

  1. Polar bears (Ursus maritimus) are the poster child for the impacts of climate change on species, and justifiably so.

    Absolutely true. They are thriving!

      • Chaswarnertoo, no need for a tasty steak. Progressives are composed of Karen-Spam (Spam that has been marinated in liberal tears). Yum! And easy on the teeth too.

  2. I’m starting a new organization: Leave the Polar Bears Alone. … How can anyone possibly count polar bears? Maybe easier than counting penguins? But why should we think about disrupting western civilization based on a very rough estimate of the number of polar bears?

    I feel we should count squirrels instead. If the number goes down, we blame climate change. If the number goes up, we blame climate change. If they can’t find their nuts, we blame climate change. Better yet, I’ll count the squirrels in my yard and just use a computer model to estimate the global squirrel count in 100 years, and then blame CO2 emissions. Of course the computer prediction could be wrong, but we MUST act now anyway, per the precautionary principle. I could get a Nobel Prize for this?

  3. Did anyone think of asking the bears if they want it warmer or colder? A quick check indicates that there are over 200,000 brown bears (not sure if this includes 50,000 grizzlies or not) indicating that they might do better in warmer climate than colder, if polar bears are an off-shoot of brown bear–rejected to the barren north for their white privilege no doubt.

    As a geologist who has worked in northern Canada bear country a lot, let me assure anyone who hasn’t–a close encounter with one of these guys will rapidly convince you that there should be one less of them.

    Nice treatment Dave, using natural history to debunk another we’re-all-gonna-die myth.

    • If the Polar Bear goes extinct, the code for them coming back is in Brown bears. So as long as Brown Bears are around so are Polar Bears. It only takes the right condition for them to reappear. Any who think different is simply is an evolution denier!

    • I worked in Yellowstone Park one summer in 1963. There were brown bears everywhere. There was a village at West Thumb at the time. Bears would wander through constantly sometimes with cubs in tow. There would often be bear jams where cars would stop to observe momma and her cub at the side of the roads. The physician at Old Faithful would be busy treating bear bites from people trying to feed the bears. At West Yellowstone there was a dump outside town. In the evening Grizzlies would gather to feed. Parking there one could see fights and incredible roaring as they fought over territory. I remember seeing one giant Grizzley male with one eye scarred over climb through the dump while the other bears scattered. I visited last summer; no bears in the park.

      • I also worked there one summer in the mid-50s for the fish hatchery which was on its way out. Same thing with bears, had one come to the cabin across the lake where we were counting and measuring the spawners going up Clear and Cub Creeks. Also been back twice, no bears, but have a picture of fresh bear scat on a trail where a camper had just had one overnight crash through his camp. Never saw that look before or since. There was a warning sign on the trail. We turned back after finding the scat. I have an old picture of a bear sticking his head in a driver side window, couldn’t get it all the way up, had to drive ahead to get rid of it.

        I have read since that black bears attack to eat you, grizzlies more for territorial reasons. Polar Bears?

          • “Not sure if you are being humorous but grizzly bear is the more common North American name for Brown Bears.”

            The National Park Service describes the grizzly to be a subspecies (U. a. horribilis) of the brown bear (Ursus arctos).

  4. From the article: “There are suggestions that before mid-century we could have a nearly ice-free Arctic in the summer. This increases the urgency with which we must act to reduce our greenhouse gas emissions to delay or avoid some of the worst consequences of climate change.”

    So we should act and spend Trillions because of “suggestions”?

    Alarmist Climate Science: Assumptions all the way down.

  5. Why are they doing so well in the Chukchi Sea? Probably more fat seals and walruses and stuff like that available. If I don’t put out bird food, the birds don’t come. If I put it out, they show up and quarrel over it. Follow the stomachs. That will tell you a lot.

    Whatever happened to the Kodiak bears? Did they all get bumped off?

    • Nope; still there Sara, but they were just more brown bears all along.

      You see, in the 19th century when biologists knew everything there was to know about grizzlies, there were 86 different species. By 1928, when they REALLY knew everything about grizzlies, there were only 7 species. By 1953 when they REALLY REALLY knew everything, there was only one. And yet by now they’re just a sub-species of brown bear after all–just like the polar bear.

      Relatively–climate science is a new field of study, and seems to be in the stage equivalent to 19th century understanding of grizzly species. But that rarely seems to deter the scientists of the day from declaring that they know all there is to know about their little universe.

      But you knew that all along; I’ve been reading your postings.

      Which reminds me–I do hope that someone has re-written the Treatise on Invertebrate Paleontology. I’d had girlfriends–of only one species–with WAY more individual variability than the many supposed separate species of trilobite I had to learn to regurgitate on exams in the 60’s. I tried to tell that to the Paleontology prof–but he was Princeton educated and would have none of it–so I regurgitated and passed, but it’s been a bit of an embarrassment ever since. I should have followed the lesson of the bears and stuck to my education by girlfriends.

    • “new field of study” – That just might explain why there is such an interest in reviving 18th and 19th century methods of cooking, preserving food, and making things work without modern conveniences.

      I look at my 300 million year old shrimp fossil and alethopteris (seed fern) fossil and ask why we can’t “get” the survival lessons they could teach us, even if they’re just iron ore concretions. All of that is right in front of us: tree leaves losing chlorophyll and “turning color” in the fall means shutting down sap production for the coming winter. Geese and ducks starting training flights as soon as the offspring are fledged out, to build endurance for the trip south, and stuffing themselves to fatten up for day-long flights south (and later on, northward), or they won’t have enough energy stores to make the flights.

      Grizzly bears moving up the slopes in the Rockies to get fat-loaded moths, to store fat for winter hibernation, and polar bears following seals and walruses around for the same thing, and people who are in “science” can’t figure out that the bears are after groceries????

      Yeah, well, those brilliant people also stated firmly that the coelacanth (an ancient fish) had died out 60 million years ago (or so), until some fishermen brought some to the surface in their fishing nets some years back. This is why I look at my 300 million year old fossil shrimp, and the dragonflies I”ve photographed, and wonder it takes to wake people up.

      If we can’t even understand the natural world on this planet, but have to squabble over it, then how will we act/react when/if we ever get to other “habitable” worlds to set up housekeeping and farming?

  6. “If sea ice is so crucial to polar bear survival, how did they survive the Eemian?”

    I’m guessing lack of Anthropogenic bullets had something to do with it.

    • Also, how did they survive the first 90% of the Holocene.

      Sea ice levels are higher now than for most of the last 10,000 years.

      Still polar bears

      And sea life is returning to the Arctic as well.

      The drop in sea ice slightly toward the pre-LIA levels has opened up the food supply for the nearly extinct Bowhead Whale, and they are returning to the waters around Svalbard.

      https://partner.sciencenorway.no/arctic-ocean-forskningno-fram-centre/the-ice-retreats–whale-food-returns/1401824

    • BobM, he shoots…he scores! I remember my first trip to Elko, Nevada, in 1973. Inside the Commercial Hotel was a giant stuffed polar bear, with a sign saying the world record. This hunting of polar bears was very trendy for the rich hunters looking for an apex predator. Remember the American Sportsman where Fred Bear hunted polar bears with bow and arrow? Fred steps out from behind an ice ridge with his bow at full draw, then raises up the arrow aim as the bear stands up, then Fred lowers the arrow and steps back behind the ice ridge and just about throws up, saying “did you see the size of that bear?”.

      • Ron Long. Being an archer since 1957 and an acquirer of Bear Archer Equipment for many years. My recollection of the American Sportsman show was that Fred shot a Silver-tip Grizzle Bear after he stalked it to within 20 yards.
        In reality Fred shot 6 bears including a Polar Bear while they were still legally hunted.
        https://www.youtube.com/watch?v=r0ds3qn-eLg
        https://www.youtube.com/watch?v=Fnj6h6U5yK8
        He also bagged a Cape Buffalo and other apex predators.

        • Carbon Bigfoot, I grew up on the side road to the local shooting/archery club. I was Oregon Instinctive boys archery-field trials, at the age of 16. Bear Kodiak bow. Since the event was on my home course I was given 6 arrows from another archer. These were the most beautiful arrows I had ever seen-what a handicap.

  7. The Polar Bears’ prey are mammals and they have to breathe air. When an area is ice covered, seals can survive by maintaining breathing holes but it’s not that easy for them. There is also the question of what the seals and walrus eat. Anyway, as you point out, the whole thing comes down to the stomach.

    The story above contains the following:

    For polar bears, being tubby is a way of life. Fat can make up 50% of their body weight; the blubber-laden seals they eat make bacon look downright healthy. Now, a new, extensive comparison of the genomes of polar bears and their closest relative, the brown bear, has revealed how polar bears survive such unhealthy diets.

    IMHO, that is clueless. In one of his books, Farley Mowat describes living in the arctic with some indigenous folks. Trying to keep up with them just about killed him and he found he craved blubber. He left the impression that he wouldn’t have survived without it. Similarly, people in the high Himalayas live on a mixture of pretty gross tea and yak butter. Similar story, some western guy thinks he was brought back to life by the stuff. Unlike Mowat, he came back to warmer climes and invented bullet proof coffee. Oh Brother! When you have to expend a lot of energy just to keep from freezing, dietary fat is rather healthy. When you’re in sunny California, you should probably limit your intake.

    I’m guessing that the Polar Bears’ diet is great for Polar Bears. Also, if I had to go a long time without eating, I think I would also pack on an extra hundred pounds of fat.

    The cholesterol levels of Eskimos and Inuit have been studied but with the assumption that their cholesterol levels should match those of the population at large. link There are confounding factors like tuberculosis and parasites so I’m not sure how much those studies tell us.

  8. I cannot understand the notion that because ‘bears were here first’, we have to tolerate them coming into town. My nearest town has a large number of neglected fruit trees, mostly apples, and it positiveely crawls with bears at this time of year. I am pretty sure the extra calories they get from fall fruit serve to increase the population density above that that would occur without the human habitation. Nowadays with increasing human population, you cannot go hiking anywhere around without bear spray, ect.

  9. Bears are an intelligent and very adaptable species (unlike climate activists). They will adapt to whatever food is most easily available, and their population will stay on the razor edge of collapse just like all populations bound by the food resource do. The only thing that kept them in check under this “starvation edge” was hunting.

    In good years the population grows and bad years it declines. This is how nature works. If there are a lot of bad years that happen to fall together, the population can crash to much smaller levels.

    If the arctic land area warms, there will be a lot of new food resources available to bears. It may be harder than whacking a baby seal head off, or grabbing an adult seal at an ice hole, but it is still food and will support some nature level of bear population.

    It takes people educated in universities to be so stupid as to not understand that nature is mean and cruel at times. They see a starving bear and panic – running to there temples of Carbon Sin and prostrating themselves in guilt. I see nature at work – the population has to come into balance with food availability. There will always be bears dying of one thing or another – all we should watch for is an unnatural change in populations. The fact the populations have grown so enormously over the past 60 years does concern me…when will the populations become unhealthy?

    • When will they become unhealthy? When they move into neighborhoods with condos and raid the local grocery stores and eyeball stray critters as lunch. Oh, wait – they do that last bit anyway. We Hoomans look might tasty to them; they’d just as soon have us for lunch as look at us. All those videos of polar bears trying to get into snowcat vehicles do not mean they’re just looking for a pat on the head.

      What the “science guys” crowd do not understand (and never will) is the REAL natural world. We mere Hoomans are simply fodder for empty predator stomachs. If coyotes roam the streets of cities like New York and Chicago (and there are plenty of videos of them), it’s because no one is allowed to shoot them and get rid of them, and declare those cities as Hooman turf.

      So, yes, there will always be bears dying of something – anything from parasitic infestations to poor hunting locally – and it’s part of the Real Natural World, which scares the pants off the science guys. They can’t control it. And they know it. And it terrifies them.

      • Speaking of coyotes I took a photo today of a coyote who looked fat and happy lounging in the yard of a small estate in south east Albuquerque. I’ve seen him before and I assume he’s being fed there and is somewhat of a pet. Years back I had a house in Topanga canyon (Santa Monica Mountains). It was the last house before Topanga State park. Lots of coyotes running through the yard. I had to put up a fence to stop them.
        Never saw bears but there was one mountain lion that I glimpsed.

      • What they do with coyotes when they wander into the city around here is catch them, give them rabies and distemper shots, make sure they’re healthy, and then send them OUT of the city. And no one in any of the counties wants them, either, so they fend for themselves on ducks, geese, deer and stray pets.
        They also get tagged (like the under-skin ID for a pet) and are sometimes fitted with radio collars so that they can be tracked.

  10. David,
    Thank God the polar bears are thriving! I’ve been so worried that they would be relegated to living off of vegan, environmental alarmists whose ships had gotten stuck in the ice whilst trying to brave the Northwest Passage! You know that that would be a very deficient diet for our poor poster children of the North! And we have seen how tough it is for PBs in Svalbard to get a decent meal without being disturbed!
    If these numbers keep increasing perhaps it will open up the possibility of legal hunting again. The black bears where I live come in a variety of colors; basic black, brown, blonde and red. It would be nice to be able to collect the full set! My apologies to Susan Crockford for any offense given!
    Obviously, these bears are apex predators that are able to survive in a wide range of habitats; from pack sea ice to frozen tundra and desolate shorelines. I would imagine they would survive quite well if dropped into temperate forests inhabited by other subspecies of brown bears like the grizzly and the Kodak!
    Once again the High Church of Climastrology has been hoisted on it’s own canard!

  11. This is the arctic sea ice today, 1 month after the (2nd lowest) minimum…

    https://seaice.uni-bremen.de/data/amsr2/today/Arctic_AMSR2_visual.png

    Just look at the Chuckchi – and the arc from there to the Barents. No ice. No ice near Svalbard. Look at Hudson Bay. No ice yet. Check this against satellite images from WorldView…

    where are the bears on that ice? either on shore or hundreds of miles from it and their denning areas….

    There is no way, never mind the population estimates of the recent past, that the current and still decreasing ice levels are not affecting populations… 2nd, 3rd and 4th lowest extents were 2016, 2019 and 2020.

    • WRONG AGAIN

      Current level is far higher than for most the last 10,000 years

      Polar bears thrived through the first 90% of the Holocene. No problem.

      Arctic sea ice has RECOVERED very slightly back to more normal Holocene levels.

      And Arctic wildlife is LUVIN’ it. !

      Not only is the land surface GREENING, but the seas are also springing BACK TO LIFE after being TOO COLD and frozen over for much of the last 500 or so years (coldest period of the Holocene)

      The drop in sea ice slightly toward the pre-LIA levels has opened up the food supply for the nearly extinct Bowhead Whale, and they are returning to the waters around Svalbard.

      https://partner.sciencenorway.no/arctic-ocean-forskningno-fram-centre/the-ice-retreats–whale-food-returns/1401824

      The Blue Mussel is also making a return, having been absent for a few thousand years, apart from a brief stint during the MWP.

      https://journals.sagepub.com/doi/abs/10.1177/0959683617715701?journalCode=hola

      Many other species of whale are also returning now that the sea ice extent has dropped from the extreme highs of the LIA. Whales cannot swim on ice. !

      https://blog.poseidonexpeditions.com/whales-of-svalbard/

      Great thing is, that because of fossil fuels and plastics, they will no longer be hunted for whale blubber for lamps and for whale bone.

      Hopefully the Arctic doesn’t re-freeze too much in the next AMO cycle, and these glorious creatures get a chance to survive and multiply.

      Why do you HATE Arctic life so much that you want to see it SUFFER from extreme high levels of sea ice like in the LIA and late 1970s, griff. ???? !!

      Quite disgusting of you.

      • “A bear will eat anything but a rock” is not much of an exaggeration. They are the apex omnivores, moreso than humans.

    • I read the title and head post of this thread and I thought…”Maybe Griff would learn something from this.”

      I was wrong!

    • “still decreasing ice levels are not affecting populations”

      WRONG AGAIN

      There is NO WAY in which the anomalously HIGH extents in the 1970s did not affect hunting on sea ice peripheries. Must have been during those few years which happened very suddenly.

      https://i.postimg.cc/4x4xCnCd/Icelandic_sea_ice_index_2.png

      You do know that is where bears hunt, didn’t you , griff.?

      If they can’t get to the sea ice edge, they can’t hunt.

      Also, Less ice allows for more ocean life, therefore more seals , therefore more PB food.

      Still one heck of a lot of sea ice up there, though.

      FAR MORE than for most of the last 10,000 years.

      And guess what..

      … there are still polar bears, in increasing numbers, as the sea ice drops back slightly towards more Holocene extents.

    • As I said Griff, I do feel sorry
      There is much less ice than in the 70s and yet there many more bears.
      An intelligent person would look at that and forced to modify their views.
      At what point do you finally start to question your beliefs?
      It’s always next year that bears will disappear?

      I worry about people like you

      You are what is wrong with the human race, no other creatures seem to birth nihilists?

  12. A single picture tells a thousand LIES …… ‘ there WERE 7 ….. today there are only 3 ….’ sums up the green readership

  13. With all the talk about the future of polar bears, nobody really knows what are the ideal climatic conditions for them. It should be clear that they do not depend so much on ice since they don’t eat ice, but on the abundance and how easy is for them to catch their prey. This suggests that ocean productivity is key. Ocean productivity is higher when the ocean is not covered by ice when the sun is shining.

    Genetic studies seem to suggest that too much cold and too much ice is bad for them. Apparently they increased in abundance early on between 800-600 kbp, but have decreased since, during the really cold conditions of the Late Pleistocene.

    Miller, w., et al., 2012. Polar and brown bear genomes reveal ancient admixture and demographic footprints of past climate change. Proceedings of the National Academy of Sciences, http://www.pnas.org/cgi/doi/10.1073/pnas.1210506109

    how did polar bears manage to survive the vast majority of the Holocene Epoch, when sea ice was far less extensive than today? For that matter, how did they survive the Eemian (Sangamonian) interglacial stage, when the Arctic was 5-10 °C warmer than it is today?

    Surviving is not the same as thriving. We do not have number estimates on polar bears prior to the 60s. For all we know the Eemian could have been a really good period to them or a really bad one. All we know is they are doing quite well in the Late Holocene. Having over 20k of an apex predator in such a harsh environment is a very respectful number. But we know they are doing well because the harsh environment has protected them from mankind, because their brown and black cousins have been decimated by us.

  14. A lot of concern about polar bears,the “poster boys ” of Climate alarmism.Not so much from the media about the horrendous slaughter of birds bats and insects by ” eco – friendly ” wind turbines.Polar bears are top – of -the- food – chain predators who will eat virtually anything,including people.Unlike bids and bats ,last time I looked.

  15. “There is no way, never mind the population estimates of the recent past, that the current and still decreasing ice levels are not affecting populations”

    ….yes, never mind facts to the contrary, I believe this.

    That’s denial 101.

    Dr. Eric V. Regehr, University of Washington 2018.

    “After a decade of research, my colleagues and I recently published the first-ever estimate of the size and status of the Chukchi Sea polar bear population, which is shared by the U.S. and Russia. And the news is good—at least for now. The bears are relatively abundant, with strong reproduction and high cub survival.”

    • Okay, so sit in your heated office in front of your computer, with a nice hot cuppa tea available, and maybe some sandwiches, and guesstimate how many polar bears there are without on-site observations that include photographs (which are valid records), and then give yerself a pat on the back.

      Yeah, that makes a lot more sense than direct observation and bear nose counting. Lots more sense. I guess it’s okay, as long as the bears are left alone.

      So what happens when the bears have migrated to another spot (like a village with a massive garbage dump, plus hunting opportunities) because there are more calories for fat-building in the garbage dumps than in the seal pods?

  16. I have a dumb question: If I can go on to Google Earth and look at my house I can tell whether the hatchback on my SUV is open or closed, why can’t these “scientists” sit at their computers and count bears in satellite images? Grant you that it might be a challenge to resolve a white critter on a white background, or a critter from a piece of ice, but that’s what image processing is for.

    • The only issue I can find with that is that bears, being mobile and moving around a lot, can distort a census count simply by moving from one place to another, and/or combining with other large groups of bears.

  17. In addition to the warmer climate the hunting pressure on Polar Bears was probably heavier during the warm early-mid Holocene than at any other time before the introduction of repeating rifles in the Arctic.

    On the (now uninhabited) islands north of New Siberian Islands there existed a most remarkable stone-age people, who lived largely by hunting Polar Bears. This is unique. For obvious reasons other arctic hunters ever since have tended to avoid Polar Bears as much as they could, but these people actually killed slightly more Polar Bears than Reindeer and very few seals:

    https://www.researchgate.net/publication/279718004_Ancient_arctic_hunters_Material_culture_and_survival_strategy

  18. First principles come first. The sea ice gives a relative advantage to denning seals, not to bears. Less sea ice means less places for seals to den, fewer places, less space over which bears must hunt. Ergo, easier pickings for the bears, less seal pups for everyone else.

    Dammit when are these frickin’ alarmists going to feel some shame for their ridiculous hypotheses that they never want to test?

  19. The “core study area” has been especially hard-hit by sea ice loss…

    Hard-hit? It does half their job for them if you too-casually employ the alarmist approach of using value-laden descriptions of purely physical phenomena. Even if done ironically, the difference may not be appreciated by normies.

  20. Why is it that climate change alarmists think polar bears need sea ice to survive? They don’t eat sea ice!

    Polar bears get most of their food supply killing seals that breed along the shore in spring. If the winter and spring are relatively mild, the ice along the shore melts earlier, and the seals come out to breed earlier, so the polar bears do not have to starve / hibernate as long over the winter. After a severe winter and/or cool spring, the polar bears have to wait longer before the seals come to breed, with the possibility of starving to death before the seals arrive.

    If the edge of the sea ice is hundreds of miles from the shore in summer, the polar bears won’t ride the sea ice waiting for an occasional fish near the North Pole. They will stay on shore, and hunt fish in shallow water or rivers on land, or small mammals that come out of their burrows in summer. If polar bears have a fatty diet as explained in the article, they need to conserve their energy, and standing by a river waiting for a fish consumes much less energy than swimming or treading water. If polar bears can interbreed with grizzly bears, as stated in the article, what prevents them from hunting like grizzly bears in summer?

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