copenlu/druid huggingface dataset:
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-02-27): London, 27 February: 2023 marked 50 years of international cooperation to protect polar bears across the Arctic. Those efforts have been a conservation success story: from a population estimated at about 12,000 bears in the late 1960s, numbers have almost tripled, to just over 32,000 in 2023. [...] Crockford added, "Western Hudson Bay and the Southern Beaufort are the only polar bear subpopulations which appeared to show strong support for the premise that sea ice declines blamed on human-caused global warming have reduced bear abundance. Now we know previous claims are almost certainly incorrect." There were no reports from the Arctic in 2023 indicating polar bears were being harmed due to lack of summer sea ice habitat, in part because Arctic sea ice in summer has not declined since 2007.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2021-07-01): A new study finds that an area of the Arctic Ocean critical for the survival of polar bears is fast becoming vulnerable to climate change. [...] Polar bears in the area use the ice to hunt for seals who build dens to raise their young on the frozen water. [...] According to the researchers, unusually strong winds moved much of the sea ice out of the area - but this was enhanced by a thinning trend, related to warming, that's been going on for years.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2022-06-16): Polar bear population discovered that can survive with little sea ice [...] An isolated population of polar bears has been discovered in southeast Greenland1, which is free of sea ice for most of the year. Polar bears (Ursus maritimus) typically need sea ice to survive, so the discovery is raising hopes that some members of the species might survive the loss of ice caused by climate change. [...] Correction 20 June 2022: A previous version of this story incorrectly stated the number of adult females in the group; and a previous version of the headline incorrectly stated that the bears could survive without sea ice.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2018-01-02): Climate change is heating up the Arctic faster than anywhere else, and sea ice is shrinking 14 percent per decade. Even today, in the middle of the bitter cold Arctic winter, satellites show there is about 770,000 square miles less sea ice than the 1981 to 2010 median (That's an area larger than Alaska and California combined). In the late spring, the ice is breaking up sooner and forming later in the fall, forcing bears to burn huge amounts of energy walking or swimming long distances to get to any remaining ice. Or they stay on land longer, spending the summer and, increasingly, the fall fasting, living off their fat from the seals they caught in the spring. [...] If these results hold up, then it shows that the loss of sea ice may have a bigger impact on the bears than previously thought, said Amstrup, a former USGS polar bear expert. Amstrup’s own 2010 study projected that continued decline in sea ice would reduce the global population of bears by two thirds, to less than 10,000 by 2050.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2022-04-12): Sea ice is essential habitat for polar bears—but across the Arctic, it is disappearing quickly. As a result of rising temperatures caused by the climate crisis, sea-ice concentrations in the Arctic have declined in every decade since the start of satellite records in 1979. The ice that remains is younger, thinner, melts earlier in spring and refreezes later in autumn. The changes we are seeing are not uniform. Polar bears are experiencing and responding to them in different ways and at different rates depending on what part of the Arctic they inhabit. Encounters between people and bears are on the rise across the region. In summer, less sea ice remains over the continental shelf, where polar bear prey are found. Many bears stay with the ice in summer and ride it north. Others come onto land to feed on the carcasses of subsistence-hunted bowhead whales. Female polar bears have shifted onto land to make their dens. [...] Svalbard is home to the fastest-diminishing sea-ice habitat among all polar bear subpopulations in the Arctic. In the last 30 years, the ice-free season has lengthened by 20 weeks. Sea ice no longer connects to some denning habitats on islands in the Svalbard archipelago. Where some bears used to be able to walk to denning locations on sea ice in autumn, they now have to swim. Polar bears here are continuing to recover from past commercial and recreational hunting.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2020-07-20): Polar bears (Ursus maritimus) require sea ice for capturing seals and are expected to decline range-wide as global warming and sea-ice loss continue1,2. Estimating when different subpopulations will likely begin to decline has not been possible to date because data linking ice availability to demographic performance are unavailable for most subpopulations2 and unobtainable a priori for the projected but yet-to-be-observed low ice extremes3. Here, we establish the likely nature, timing and order of future demographic impacts by estimating the threshold numbers of days that polar bears can fast before cub recruitment and/or adult survival are impacted and decline rapidly. Intersecting these fasting impact thresholds with projected numbers of ice-free days, estimated from a large ensemble of an Earth system model4, reveals when demographic impacts will likely occur in different subpopulations across the Arctic. Our model captures demographic trends observed during 1979–2016, showing that recruitment and survival impact thresholds may already have been exceeded in some subpopulations. It also suggests that, with high greenhouse gas emissions, steeply declining reproduction and survival will jeopardize the persistence of all but a few high-Arctic subpopulations by 2100. Moderate emissions mitigation prolongs persistence but is unlikely to prevent some subpopulation extirpations within this century. [...] Rode, K. D., Amstrup, S. C. & Regehr, E. V. Reduced body size and cub recruitment in polar bears associated with sea ice decline. Ecol. Appl.20, 768–782 (2010). [...] Bromaghin, J. F. et al. Polar bear population dynamics in the Southern Beaufort Sea during a period of sea ice decline. Ecol. Appl.25, 634–651 (2016).
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2019-01-04): We’ve long known that sea ice is an important platform for polar bears to hunt and raise young, but it turns out that the ice itself also carries a valuable energy source. [...] If you’re now picturing massive jaws chowing down on a crunchy icy meal covered in green slime, no, that’s not it. Polar bears do not eat sea ice directly. Instead, researchers found that the majority of polar bears’ diet is made up of critters that ultimately depend on sea-ice algae as a food source. Their study examined polar bears from Baffin Bay, western Hudson Bay, and southern Hudson Bay. [...] Sea ice is already known as important habitat for polar bears. "But what if we’re not seeing the whole picture, and what if sea ice is more important than we’re giving it credit for?" says Brown. "Less sea ice means less habitat, not only for polar bears but, importantly, also for the sea ice microorganisms that form a big part of the very base of the bear’s food chain," he says.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2023-01-27): - Andrew Derocher, Jan. 17, Email exchange with USA TODAY interviewed him but a quote didn't make the cut - Dag Vongraven, Jan. 18, Email exchange with USA TODAY - Ecological Applications, Jan. 10, 2020, Interrelated ecological impacts of climate change on an apex predator - International Union for Conservation of Nature, 1966, Proceedings of the first international scientific meeting on the polar bear - International Union for Conservation of Nature, 1985, Polar bears: proceedings of the eighth Working Meeting of the IUCN/SSC Polar Bear Specialist Group, held at the Ministry of Environment, Oslo, Norway, 15-19 January 1981 - Polar Bear Specialist Group, July 2021, Status Report on the World’s Polar Bear Subpopulations - John Whiteman, Jan. 20, Phone interview with USA TODAY - Kristin Laidre and Nicholas Lunn, Jan. 20, Email exchange with USA TODAY - NASA, Feb. 4, 2020, Polar Bears Struggle as Sea Ice Declines - Polar Bears In Canada, accessed Jan. 20, Guided Hunting in Canada - Polar Bear Range States, accessed Jan. 20, The 1973 Agreement on the Conservation of Polar Bears - Steven Amstrup, Jan. 17, Email exchange with USA TODAY - AFP, Jan. 13, Graph on polar bear population uses unreliable data
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2023-12-06): Current polar bear populations 22-31,000 polar bears worldwide, estimated [...] By 2040, scientists predict that only a fringe of ice will remain in Northeast Canada and Northern Greenland when all other large areas of summer ice are gone. This "Last Ice Area" is likely to become important for polar bears and other life that depends on ice. A projection of sea ice in the archipelago, supported by WWF, shows that much of the region is facing significant ice loss in the coming decades – with potentially serious consequences for polar bears.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-08-21): Polar Bears and Arctic Sea Ice Polar bears roam across the circumpolar Arctic, where they rely on sea ice to reach their seal prey. But not all sea ice is equal. Learn about the four sea ice ecoregions, how the quality of sea ice differs across the polar bear’s range, and how we can help ensure the bears’ future by addressing climate change. [...] The number of polar bears worldwide is not increasing. Some populations are recovering after their numbers were vastly reduced by uncontrolled hunting in the 1960s, but that potential for growth is running head first into declining carrying capacity in some regions due to loss of sea ice habitat.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-02-13): Some polar bears face starvation as the Arctic sea ice melts because they are unable to adapt their diets to living on land, scientists have found. [...] There are about 26,000 polar bears left in the world, with the majority in Canada. Populations are also found in the US, Russia, Greenland and Norway. [...] "It is likely polar bears will disappear from areas where sea ice will be lost in future, but difficult to say just when and where," said Jon Aars from the Norwegian Polar Institute who was not involved in the study.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2023-11-13): Rising sea temperatures lead to reduction in polar bears since the last ice age [...] We see a disturbing link between population decline and environmental changes. A relatively small increase in the sea surface temperature, and in turn a small reduction sea ice, resulted in a rather dramatic decline in the population of the polar bear. [...] "We see a disturbing link between population decline and environmental changes. A relatively small increase in the sea surface temperature, and in turn a small reduction sea ice, resulted in a rather dramatic decline in the population of the polar bear. The relationship is not linear," continues Eline Lorenzen.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2020-07-20): Scientists say some populations have already reached their survival limits as the Arctic sea ice shrinks. [...] Studies show that declining sea ice is likely to decrease polar bear numbers, perhaps substantially. The new study, published in Nature Climate Change, puts a timeline on when that might happen. [...] Sea ice is frozen seawater that floats on the ocean surface, forming and melting with the polar seasons. Some persists year after year in the Arctic, providing vital habitat for wildlife such as polar bears, seals, and walruses.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2020-05-18): Incorrect: The claim that "Polar bears are thriving even where sea ice is diminishing" runs counter to scientists’ understanding: sea ice loss due to climate change is recognized as the most important threat to the long-term survival of polar bears. [...] Overall, the claims that the polar bear population is growing and that polar bears are thriving in areas where sea ice diminishing are not supported by scientific evidence. [...] For the claim that "Polar bears are thriving even where sea ice is diminishing"—again, this is spin. In Western Hudson Bay, Southern Hudson Bay, and Southern Beaufort Sea, population declines are associated with sea ice loss (lower survival, lower successful reproduction that lead to abundance declines). Some polar bear populations are doing OK and are experiencing some sea ice loss. We know, however, that that pattern cannot be sustained. The Barents Sea polar bears appear to be doing OK yet they are losing sea ice at high rates. Why are they doing OK and others are not? That area has a very large area of continental shelf/shallow water. Polar bear habitat is widespread. It is experiencing the highest rate of sea ice loss in days of cover per decade of the 19 polar bear populations. We’ve just not hit the point where their habitat is affected enough to cause problems. It will happen. Regardless, this area has seen many changes (e.g. loss of maternity den areas, loss of habitat). I worked in the Barents Sea for 7 years—this population will lose with the current trend in sea ice.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2022-12-08): The consensus is clear – as Arctic sea ice melts, polar bears are finding it harder to hunt, mate and breed. While polar bears have shown some ability to adapt to changes in their surroundings – for example, by foraging for food on land, or swimming more to hunt for prey – scientists project that as sea ice diminishes, polar bears will find it harder to survive and populations will decline. [...] Polar bears depend on sea ice for most important aspects of their lives – including hunting, mating and resting. While polar bears are strong swimmers, capable of swimming for hours on end, they find swimming much more energy intensive than walking. As such, sea ice is crucial for polar bears to survive. [...] While polar bears have shown some ability to adapt to changes in their surroundings – for example, by foraging for food on land or swimming more to hunt for prey – scientists project that polar bears will become more food-stressed as sea ice diminishes and that populations will decline.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-07-18): Across recent history, the sea ice was generally stable, thick and not noticeably in retreat. With stable habitat, polar bears were a renewable resource that could be harvested on a sustainable basis. [...] Polar bears depend on the sea ice surface to efficiently catch their seal prey. A shorter duration of ice cover over their productive hunting areas means less opportunity to hunt. A reduction in sea ice has been statistically linked to reduced stature and weight in polar bears and to lower survival rates of cubs. So, it doesn't really matter that hunting is now largely under control or that we know a lot about other impacts people might have on bears. Without habitat, polar bears will disappear no matter what else we do. [...] Planetary physics requires the world to warm as greenhouse gas concentrations rise, so without greenhouse gas mitigation, the ice will continue to melt. For an animal dependent on sea ice to survive, the prospects are not good. As the ice decline continues, the plight of the polar bear can only worsen.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2019-06-28): This article in the opinion section of Financial Post, written by Susan Crockford, claims that rather than being threatened by declining Arctic sea ice, polar bears are "thriving". [...] Castro de la Guarida1 states, "Sea ice across the Arctic is declining and altering physical characteristics of marine ecosystems. Polar bears (Ursus maritimus) have been identified as vulnerable to changes in sea ice conditions. We use sea ice projections for the Canadian Arctic Archipelago from 2006 – 2100 to gain insight into the conservation challenges for polar bears with respect to habitat loss using metrics developed from polar bear energetics modeling. PRINCIPAL FINDINGS: Shifts away from multiyear ice to annual ice cover throughout the region, as well as lengthening ice-free periods, may become critical for polar bears before the end of the 21st century with projected warming. Each polar bear population in the Archipelago may undergo 2-5 months of ice-free conditions, where no such conditions exist presently. We identify spatially and temporally explicit ice-free periods that extend beyond what polar bears require for nutritional and reproductive demands. CONCLUSIONS/SIGNIFICANCE: Under business-as-usual climate projections, polar bears may face starvation and reproductive failure across the entire Archipelago by the year 2100."
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-01-01): Polar bears live in one of the world’s harshest environments: the Arctic. Roaming across sea ice, polar bears peer through cracks in the ice to look for ringed seals, their favorite food, in the water below. Almost all of a polar bear’s food comes from the sea, and includes seals, fish, and even beluga whales. The floating sea ice is a perfect vantage point for the bears as they hunt for food. Unfortunately, the amount of sea ice floating in the Arctic region is shrinking each year. The ice is melting as the Earth is warming. Within the next couple of decades, there may be no more sea ice in the Arctic Ocean during the summer.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2023-11-08): Nevertheless, a new study highlights that this trend has deep historical roots, with polar bear numbers in Greenland diminishing over a period of 20,000 years. [...] "It's the rising sea temperatures that drive the decline in the polar bear population. When the sea temperature rises, there is less sea ice, and consequently, fewer seals, which polar bears feed on," explains Michael Westbury. [...] "We see a disturbing connection between population decline and environmental changes. A relatively small increase in water temperature and a small reduction in the amount of sea ice result in a quite dramatic decline in the polar bear population. The relationship is not linear," Michael Westbury continues.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-07-18): Polar bears depend on the sea ice as a platform for hunting seals, the mainstay of their diet. They also rely on the sea ice for breeding, roaming, and sometimes denning. But the most significant thing to understand is that sea ice is far more than a platform: It's an integral part of the Arctic ecosystem. Sea ice is the "soil" for the Arctic marine food web. As the salty ocean water freezes, the salt is pushed out, creating briny channels and pockets underneath the ice. Tiny microorganisms thrive and grow in this unique environment. These small organisms play a key role in the Arctic food chain, creating a food base for Arctic cod, which then feed ice seals, which then feed polar bears. [...] Rather than being distracted by thoughts of fake ice or floating platforms, societies around the world need to act with urgency to halt global warming. If we don’t, sea ice ultimately will disappear and so will polar bears. We view the situation of diminishing sea ice in the Arctic as extremely serious but not hopeless. The key to saving sea ice and getting our climate back to functioning the way it should is to move away from using fossil fuels like oil, gas, and coal altogether, shifting instead to energy sources like wind, solar, and water. As this shift is underway, we can also help by embracing energy efficiencies that reduce our use of fossil fuels and by choosing green energy options if they’re available in our communities.
Claim: The polar bear population has been growing. Polar bears are thriving even where sea ice is diminishing. (Anonymous, 2020-05-05)
Evidence (2024-09-10): The bears can’t thrive on land, a concerning discovery as sea ice continues to disappear at a rapid pace, a new study says. For the polar bears of Manitoba, Canada, the sea ice that envelops western Hudson Bay for most of the year is the ideal hunting ground for a feast of blubber-rich seals. But then come the dog days of summer, when the ice melts and the bears are forced onto land. There, life is no picnic for these giant creatures. [...] Polar bears live in 19 regions across the Arctic, from Canada to Greenland to Russia. While some populations live on permanent ice, others inhabit seasonal ice. Climate change has caused ice loss to some degree in all the regions, leading to drastic population declines. As a result, the International Union for Conservation of Nature lists polar bears as vulnerable to extinction.