Articles tagged with Bears
A study found that Chukchi Sea polar bears spent more time on land during summer sea ice loss, with minimal access to preferred prey. The increased land use may lead to increased nutritional stress and human-polar bear interactions.
A WSU study suggests linking isolated wildlife sanctuaries by a national network of protected river corridors to provide animals with connected habitats. The research builds on existing environmental policies, including the Clean Water Act and Endangered Species Act.
New calculations indicate that polar bears can survive on land-based food sources, such as caribou and snow goose eggs, to avoid starvation due to ice melt. The research found that these alternative food sources provide enough calories for bears to sustain themselves during extended stays on land.
Scientists solve the mystery of polar bear Knut's encephalitis, a rare autoimmune disease previously known only in humans. The discovery provides new insights into the possible prevalence of autoimmunity in humans and other mammals.
A study by UC San Diego biologists found that black bears in Yosemite National Park primarily forage on plants and nuts, with acorns and pine nuts being their main food sources. The research also suggests that female bears tend to forage more heavily for high-fat seeds during reproduction.
Researchers found that bears' heart rates increase significantly when exposed to unmanned aerial vehicles, a sign of acute stress. Despite the calm behavior observed in encounters with UAVs, the physiological response is notable, with one bear's heart rate increasing by up to 400 percent.
Scientists use new technology to determine grizzly bears' protein intake and mercury levels by analyzing a single hair sample. The technique has potential applications in determining the recovery of threatened bears and their habitat needs.
A new study finds polar bears experience limited energy savings in summer due to the ongoing loss of sea ice. Despite initial hopes that they could compensate for food deprivation through modified activity and metabolic rates, researchers found no evidence of such adaptations.
New research reveals polar bears' metabolic rates remain high during summer ice melt, limiting their ability to conserve energy. The study suggests that as sea ice loss increases, polar bears are unable to adapt by entering a low-energy state, leaving them vulnerable to food shortages and reduced survival rates.
Researchers found that hibernating black bears suppress resorption of bone tissue to maintain their skeleton, protecting bones by reducing resorption. This discovery provides insights into how these animals conserve energy and bone mass during long periods of inactivity.
A new study published in Nature Climate Change suggests that climate change will not lead to widespread interbreeding among closely related species. Only about 6 percent of species with non-overlapping ranges are likely to come into contact by the end of this century.
Bioethicists can help reframe climate change discussion to focus on serious health risks, rather than just polar bears or environmental issues. This approach could aid communication efforts and mitigate tensions between skeptics and experts.
Researchers have developed genetic maps that reveal ancient migration patterns of black bears in North America, providing insights into their evolution and distribution. The study identifies four glacial refugia where bears retreated during ice ages and shows how they dispersed into different regions.
A recent study highlights the growing threat of environmental contaminants and plastic pollution to polar bear health, alongside climate change. The research, led by Norwegian scientists, found that exposure to these pollutants is affecting the endocrine system and reproductive system of polar bears.
A study by USGS scientists found that polar bears are increasingly forced to eat terrestrial foods like berries, birds, and eggs due to sea ice loss. However, these alternative food sources provide limited nutritional benefits for the bears.
A recent study refutes claims of an unknown bear type in the Himalayas that inspired yeti legends. Genetic analysis suggests the samples attributed to an unknown species were actually from ordinary Himalayan Brown Bears.
Researchers found that ant-scaring insects, like beetles, allowed treehoppers to thrive, benefiting nearby rabbitbrush plants. This study highlights the interconnectedness of species in ecosystems and the importance of conservation.
Polar bears may undergo 2-5 months of ice-free conditions by 2100, threatening their survival. Projected warming under business-as-usual climate projections could lead to significant habitat loss for nearly one-tenth of the world's polar bear habitat.
Scientists investigated how scent communication affects polar bears, which is vital for reproduction and social behavior. The study suggests that climate change may disrupt this communication, threatening the species' survival.
Researchers studying grizzly bears have discovered a natural state of diabetes that serves a biological purpose and is reversible. Grizzlies become diabetic only weeks after hibernation, but then recover when they wake up in the spring. The study reveals how natural biology can teach us about animal coping mechanisms with diseases.
A comprehensive study found that black bears in the Central Interior Highlands (CIH) have a remnant lineage in the northern Ozarks of Missouri, indicating their presence throughout the region. The reintroduction of bears in the 1950s and 1960s helped restore diversity and increase population size in the Ozarks and Ouachitas.
A novel First Nations-led study uncovers a previously undocumented grizzly bear 'highway' in coastal British Columbia, revealing nearly 60 individual bears aggregated in the Koeye River. The research also provides early evidence of declining bear populations linked to salmon scarcity.
A study published in PLOS ONE uses satellite images to estimate polar bear population sizes, finding similar results to aerial and ground surveys. The technology holds promise for tracking Arctic wildlife, despite logistical challenges.
A team of engineers developed an optimization algorithm inspired by salmon migration patterns, successfully solving 25 benchmarking problems and finding optimal solutions for laser setup. The Great Salmon Run (TGSR) algorithm outperformed conventional genetic algorithms in most cases, converging faster to optimal solutions.
Caswell's work on matrix population models has had a significant impact on life history theory, conservation biology, climate studies, and the evolution of aging. He was recognized for his lifetime contributions to mathematical demographic analysis.
A recent genome study has found that polar bears rapidly evolved the ability to consume a fatty diet without developing heart disease due to mutations in cardiovascular function genes. The study also reveals that polar bears diverged from brown bears less than 500,000 years ago.
A genome comparison reveals polar bears' rapid evolution to cope with a high-fat diet, providing insight into fatty acid metabolism and cardiovascular function. The study's findings may offer tools to modulate human physiology and protect against the ill effects of high-fat diets.
Researchers analyzed 79 Greenlandic polar bears and 10 brown bears to uncover genes involved in the polar bears' adaptation to life in the high Arctic. The study found that the polar bear diverged from brown bears less than 500,000 years ago and developed unique adaptations to cope with a high-fat diet.
A new study on brown and polar bears found extensive male gene flow leading to the distribution of similar Y chromosomes across vast distances. The research estimated the split between male lineages of brown and polar bears to around 0.4-1.1 million years ago, confirming they are distinct species.
Researchers analyzed chemical isotopes in hair and bone samples to track changes in Yosemite bears' diets over the past century. Management strategies implemented since 1999 successfully limited human food availability, but problems persist, with bears returning to dumpsters despite increased visitor numbers.
Research finds polar bears have unique genetic variations that influence nitric oxide production, a key factor in energy metabolism and thermogenesis. This adaptation enables them to survive the harsh Arctic environment without hibernation.
Researchers have established a new biomarker for stress in wild animals, using hair cortisol concentration (HCC) to monitor polar bears affected by global climate change. The technique has been successfully applied to analyze cortisol levels in polar bear hair samples from the past century.
Researchers found that fur coats and down feathers derive their insulating power from an optical mechanism involving the scattering of infrared light. This discovery could lead to improved building insulation and the development of new types of ultrathin insulation.
Researchers found that some polar bears in the western Hudson Bay population are using flexible foraging strategies, such as prey-switching and eating plants and animals. This behavior may help them survive in a rapidly changing environment where sea ice is melting earlier and freezing later.
Research reveals steep declines in global large carnivore populations, with 77% of studied species decreasing in number. Habitat losses have serious environmental consequences, affecting ecosystems and human societies.
Etienne Benson's research reveals that squirrels were intentionally introduced to cities in the 19th century as part of a parks movement aimed at beautifying urban landscapes. The presence of squirrels in cities is linked to the idea that nature in the city is essential for human health and sanity.
A 10-year study found that warmer temperatures and forest disturbances helped grizzlies build more body fat, increasing their chances of successful reproduction. This 'silver spoon effect' benefits bears born into favourable conditions, giving them a head-start in life.
A study by Imperial College London finds that EU law could reduce tolerance for brown bears in Croatia, leading to increased conflict between humans and bears. The current system involving hunting ensures local support for the animals' survival, but EU legislation may disrupt this.
Researchers found that polar bears have switched to sub-Arctic seals with higher contaminant loads, which contradicts the expected improvement in their condition. The shift is linked to climate change and the melting of Arctic sea ice, posing long-term risks to the polar bears' access to food.
A study by Montana State University researchers found that the 25 wildlife crossings on the Trans-Canada Highway in Banff allow grizzly bears to access a prime patch of buffalo berries habitat safely. The crossings also enable bears to move between food, shelter and dispersal areas on both sides of the highway.
A new study reveals that wolves' re-introduction to Yellowstone National Park has led to a resurgence of berries in the grizzly bear's diet, helping them gain weight before hibernation. The recovery of trees and shrubs has improved the bears' health and ecosystem balance.
Researchers have detected perfluoroalkyl substances (PFASs) in the brain tissue of polar bears, which could have severe impacts on human health. The study suggests that PFASs are crossing the blood-brain barrier and accumulating in all parts of the brain, highlighting the need for further research into their effects.
A study by University of Missouri-Columbia biologists reveals that hundreds of black bears inhabit southern Missouri's Ozark forests, indicating a return to healthy forests. The bear population is small but growing, and experts warn of potential conflicts with outdoor recreationists and homeowners.
Researchers have characterised new sequences of endogenous retroviruses in polar bears and pandas, dating back 45 million years. The viruses are suspected to play a role in human diseases such as cancer and neurodegenerative disorders.
Research suggests that fragmented pine stands hinder seed production, reducing regeneration. Whitebark pines' viability depends on pollen release, wind, and proximity, making their future uncertain with dwindling gene pools.
A new study reveals that Nevada's black bear population is increasing and expanding its former range due to conservation efforts. The study analyzed historic records and found that the bears were once widespread but vanished by 1931, only to rebound in recent years.
Polar bears in western Hudson Bay are forced to adapt to earlier summer sea ice break-up and later fall departure due to climate change. The timing of their migration can be predicted by sea ice melt and freeze patterns, affecting their health and cub production.
A study on polar bears in western Hudson Bay found that the timing of their migration can be predicted by sea ice melt and freeze patterns. The results suggest that as sea ice melts earlier and freezes later, polar bears arrive on shore earlier in the summer and leave later in the autumn.
A new study published in PLOS Genetics found that brown bears on Alaskan archipelago descended from polar bears through hybridization, not the other way around. The research used DNA sequencing to analyze the X chromosomes of the brown bears and found that 6.5% of them had recently come from polar bears.
A new genetic study has overturned previous ideas about the evolutionary history of polar bears and brown bears. The research found that a population of brown bears on Alaskan islands had a remarkable history of hybridization with polar bears, resulting in striking genetic similarities between the two species.
A distributed biological observatory in the North American Arctic will monitor the biological response to sea ice retreat and environmental changes in the Bering and Chukchi Seas. The project aims to track how Arctic creatures respond to climate change and understand its effects on higher organisms.
Polar bears face an imminent threat from rapid Arctic ecosystem changes, which could lead to population declines of up to 50%. Governments must develop conservation plans to mitigate the effects of climate change. The authors' study suggests that a single severe ice year could erase half of a polar bear population in a single year.
A four-year study found that young grizzly bears learn their habitat selection strategies from their mothers, which may be a more adaptive strategy than instinct. The research tracked 32 adult and young bears in western Canada and showed genetically related female bears shared similar habitat choices.
Research shows that preserving a mix of streams with different temperatures supports salmon reproduction and provides an all-summer buffet for brown bears and gulls. This diversity allows predators to access salmon for up to three months, rather than just a few weeks.
A study published in Veterinary Record compares the athletic abilities of humans and animals, finding that greyhounds, cheetahs, pronghorn antelope, and other species outrun and outmuscle top athletes. Human adaptations for endurance are impressive, but animals excel in speed, strength, and power.
A new DNA study provides clues about the species' evolution, suggesting that climate change and genetic exchange with brown bears helped create the polar bear as we know it today. The research found evidence of fluctuating population sizes over the past million years, growing during cooling periods and shrinking in warmer times.
Increasing escapement can improve the natural environment by benefiting grizzly bears, who will consume more salmon and occur at higher densities. This leads to a better environment for salmon, with more discarded salmon entering downstream life and enriching the ecosystem.
A Norwegian University of Science and Technology study found that polar bear cubs in Svalbard have lower blood levels of PCBs and related contaminants, indicating a decline in exposure to these toxic chemicals. The levels of contaminants in mother bears' blood also decreased, suggesting reduced transmission from mothers to their cubs.
A new study by researchers at the University of Alberta found that the ranchland near Pincher Creek is a hot zone for grizzly bear encounters. Despite no human fatalities, the area's private land and cattle carcasses attract bears.
Researchers at Brigham Young University found that carrying guns in bear encounters offers no protection and can lead to increased injuries. Instead, they recommend using bear spray as a safe alternative. The study analyzed 269 incidents of bear-human conflicts and found that firearms did not reduce the risk of injury or fatality.