Articles tagged with Bears
A team of scientists has discovered that the female ancestor of all living polar bears was a brown bear that lived in Britain and Ireland during the last ice age. This hybridization event likely occurred due to climate changes affecting the North Atlantic ice sheet, leading to periods of overlap in bear habitats.
A study in Current Biology found that polar bears and brown bears have mated successfully for 100,000 years, resulting in unexpected genetic connections between the two species. The research suggests that climate change may be responsible for these hybridizations, which could impact conservation strategies.
Research reveals that lone male black bears are the primary cause of fatal attacks on humans, with a significant increase in attacks linked to human population growth. The study also found that familiarization with humans and previous bear encounters do not necessarily lead to increased attack rates.
A new study by University of Calgary researchers shows that human activity displaces predators more than prey in the food chain. By limiting human use of roads and trails to less than 18 people a day, the negative impact on wildlife food webs can be reduced.
Researchers discovered that Alaskan black bears only reduce their body temperatures slightly during hibernation, yet experience a dramatic decline in metabolic activity, slowing to 25% of normal rates. The bears' metabolism remained suppressed for several weeks after emerging from hibernation.
Black bears experience large decreases in metabolism during hibernation, with metabolic rates remaining suppressed for several weeks after emergence. This finding has significant implications for potential applications in emergency medicine, such as reducing metabolic demand in patients experiencing stroke or trauma.
Researchers link declining litter sizes to loss of sea ice in Hudson Bay, predicting significant threat to western polar-bear population. Climate change could reduce energy availability for pregnant females, leading to failed births or natural abortions.
Research on grizzly bears reveals a complex series of changes in their hearts as they hibernate, including the adaptation of a protein called myosin heavy chain. The left atrium produces more alpha protein, resulting in a weaker beat, to prevent damage from pushing against the stiffened ventricle.
Researchers found that polar bear populations could decline by two-thirds by mid-century, but emissions reduction can mitigate this. Sea ice habitat won't face a catastrophic 'tipping point' under mitigation scenarios.
A new USGS study models the impact of reduced greenhouse gas emissions on Arctic sea-ice loss and polar bear habitats. The research indicates that lowered emissions could help preserve polar bears in all four ecoregions where they exist, reversing projected declines in population size.
New research indicates that if greenhouse gas emissions are reduced substantially, enough Arctic ice may remain for polar bears to survive. The study found no 'tipping point' beyond which summer sea ice loss would be unstoppable, offering a hopeful message but also an incentive to mitigate emissions.
Biologists report that polar bears are unsuited for alternative diets in a warmer world, where they will come into competition with grizzly bears. The study suggests that polar bears' weaker skulls make them less competitive for resources.
Large predator species like tigers and polar bears are more vulnerable to environmental changes than smaller species due to their high energetic costs. They require more energy to find food, making them more susceptible to population declines.
Researchers found that polar bears can thrive even if they raid geese nests, thanks to a mismatch in timing that allows geese to lay eggs earlier than bears arrive on shore. This means the geese population is unlikely to go extinct despite bear predation.
A study found that female bears with cubs and independent young bears in the Cantabrian Cordillera do not enter hibernation. In contrast, older bears, including females preparing to give birth, exhibit typical hibernation behavior.
Researchers discovered a nearly complete jaw from the hyena-like animal, Palaeonictis wingi, which evolved to half its ancestors' size during a 200,000-year period of global warming. The study suggests other factors may have played a critical role in its evolution.
An international team of scientists has found that the decline of the cave bear started 50,000 years ago due to human expansion and competition for land. The study analyzed mitochondrial DNA sequences from 17 new fossil samples and compared them with modern brown bears.
Researchers explore alternative visual strategies to engage the public with climate change, highlighting the need for inspirational motifs and renewable energy icons. Climate scepticism and knowledge gaps pose significant challenges in addressing climate change, requiring creative communication approaches.
Researchers tracked timber rattlesnakes to understand how wildlife habitats are affected by human encroachment. They found that even modest roads have a significant effect on genetic diversity, making populations more susceptible to illness or environmental changes.
A team of scientists predicts that warmer temperatures in the Arctic will create challenges for seabirds' nesting habits. The study found that increasing storm events, heavy fog, and wet snow will impact birds adapted to cold, dry summers, making them more susceptible to mortality.
Researchers sequenced ancient genome from a rare fossil, confirming polar bears are an evolutionarily young species that split from brown bears 150,000 years ago. The study found polar bears adapted rapidly to past climate changes, but their adaptability is uncertain in the face of current and future climate change.
A rare ancient polar bear fossil has yielded essential information about the species' evolutionary history and response to past climate changes. The research confirms that polar bears evolved recently and adapted quickly, with a split from brown bears around 150,000 years ago.
Biologists have found grizzly bears roaming into traditional polar bear habitat in Wapusk National Park, increasing competition and potential predation on polar bears. The sighting of grizzlies was rare before 1996, but sightings have increased since then.
Researchers found scant evidence of antibiotic resistance genes in isolated polar bears, contradicting previous findings in other animals. The study suggests that the spread of antibiotic resistance may be caused by human contact, rather than natural occurrence.
A long-term study found polar bears in the southern Beaufort Sea are shifting their habitat use from sea ice to land and open water, increasing human-bear interactions. The study, conducted between 1979 and 2005, shows a significant increase in bear sightings on land and in open water.
A new study led by the University of Michigan reveals that polar bears get their nutrition from two main food webs: phytoplankton-based and ice algae-based. The research found that those who primarily eat phytoplankton have higher mercury concentrations, highlighting the importance of understanding Arctic ecosystems.
A recent study published in PLoS ONE found that French brown bears are at risk of extinction due to a lack of females. The researchers suggest that relocating new bears could not only boost the population size but also reverse some of the causes of the decline by introducing more females.
Researchers have found northern brown bears feeding on migrating broad whitefish in a stream in the Mackenzie Delta region. This discovery highlights the importance of considering the impact of development activities on these bears' diets and survival.
A study published by Montana State University researchers found that elk are having fewer calves due to changes in their nutrition, mainly caused by the presence of wolves. Elk are changing their behavior and foraging habits, such as browsing more in forested areas, resulting in a 27% decrease in food intake.
A University of Minnesota-led study finds that sport hunting is depleting lion and cougar populations, with management agencies often prioritizing human safety over conservation. The study suggests that new approaches are needed to protect humans and livestock while managing sport hunting.
New research shows that polar bears can adapt to a changing Arctic by consuming snow goose eggs, which are rich in nutrients. As the Arctic warms, the timing of sea-ice breakup and snow goose nesting is shifting, providing an alternative source of food for subadult males.
The USGS discusses prehistoric climate changes providing clues to future shifts and large deposits of gas hydrates on Alaska's North Slope. Holiday lights reveal the mineral composition behind their glow.
Scientists have revised the timeline of cave bear extinction, dating it back 27,800 years. The new findings suggest a link between climate change and food supply loss, leading to the demise of these massive mammals. Researchers found no evidence of human involvement in their disappearance.
Researchers found water bears can withstand extreme dehydration and cosmic radiation in space, but are harmed by ultraviolet radiation. Ingemar Jönsson's team discovered that water bears can repair DNA damage after exposure to space conditions.
A study published in INFORMS journal Interfaces found that US polar bear research is flawed due to inadequate forecasting methodologies. The researchers concluded that the studies do not adequately support assumptions about sea ice changes and polar bears' ability to adapt, making it difficult to justify listing the species as endangered.
Researchers found that black bears acquire behavior to conflict with humans through social learning and isolation, challenging the assumption that mother bears teach their cubs. The study indicates that 56% of mothers did not share behavioral habits with their offspring.
A new study by Brigham Young University shows that bear spray is an effective deterrent against bears, with a success rate of 92% in halting aggressive behavior. The study also found that running away from bears can actually attract them, and users should take precautions when using the product.
A recent study published in PNAS found that Spanish brown bears have genetic material from bears in other parts of Europe, challenging the idea of their isolation. The research, led by Anders Götherstam and Cristina Valdiosera, analyzed DNA sequences from prehistoric material and discovered a unexpected pattern.
New research reveals that Pleistocene cave bears were as omnivorous as modern bears, eating both plants and animals. This challenges previous studies that suggested they were largely vegetarian.
Researchers found that stress hormone noradrenaline suppresses pain inputs from the brainstem, reducing neurotransmitter launch and triggering nerve impulses. The study provides important mechanistic clues to understanding stress-induced analgesia.
A recent study published in Molecular Ecology reveals that the genetic distribution of brown bears was not solely determined by Ice Age isolation. Instead, human hunting and land use have had a significant impact on their genetics, allowing them to survive and thrive in central Europe during the coldest periods. This new understanding ...
In a study by the Wildlife Conservation Society, pregnant moose have shifted their movements to closer roads and infrastructure to avoid predation of their calves. Moose mothers use humans as a shield from grizzly bears and other predators due to human behavior.
Scientists identified how brain responds to an approaching menace, shifting from strategic areas to reactive responses. The study found that the closer a threat gets, the more impulsive the response, reducing free will.
The Wildlife Conservation Society's 'Warm Waters for Cool Bears' project uses satellite imagery and meteorological data to predict where sea ice will persist, enabling conservation efforts. The study aims to inform management activities such as designating protected areas for polar bears and their prey species.
A new study found that hibernating black bears lose about half as much skeletal muscle strength as humans confined to bed rest for similar periods. The researchers tested the bears' muscle strength and fatigue resistance after a 110-day period of anorexia and confinement.
A DNA study on ancient cave bear teeth found a sudden replacement of the mitochondrial DNA sequence around 28,000 years ago in the Ach Valley. The new genetic group is believed to have originated from neighboring bears who infiltrated the area after human migration and eventually became extinct.
A new study found that grizzly bears in the foothills of Alberta have a varied diet, eating everything from ants to moose and berries. The research team identified 40 different food items, with moose being the most common prey, and found that the bears' activity patterns vary depending on the season and environment.
Polar bears' habitat preferences shift as sea ice declines, affecting prey availability and reproduction. USGS research shows a causal link between earlier sea ice breakup and decreased polar bear survival.
Researchers from NASA and the Canadian Wildlife Service found that climate warming is negatively impacting polar bears due to shorter spring hunting seasons and reduced sea-ice cover. This can lead to a decline in female reproduction, reduced body weight, and increased human-bear conflicts.
A new airborne radar system measures snow depth on Arctic sea ice, aiding climate change research and understanding polar bear habitats. The project validates satellite measurements and provides insights into the region's climate and wildlife.
A study by Professor IV Yannas suggests that adults have a dormant regenerative potential that can be reactivated with the right agents. This discovery may lead to new treatments for organ regeneration and increased longevity. The emerging field of Regenerative Medicine is based on this new treatment.
Researchers found a significant difference in POP concentrations between grizzlies with and without a steady diet of salmon. The study suggests that the reproductive window of these bears may be vulnerable to health impacts due to the high contaminant levels.
Researchers have discovered evidence of barren ground grizzly bears on Melville Island, a remote area in the western Arctic. The presence of these bears is significant as they are known to prey on polar bear cubs and could potentially disrupt the balance of Arctic ecosystems.
A new fossil discovery in Edmonton provides crucial insights into the evolution of brown bears in North America. The ancient fossil, dated to around 26,000 years ago, reveals that brown bears migrated south of Beringia much earlier than previously believed, with some populations reaching as far as southern Canada and the northern US.
The study identifies areas with high mortality rates among grizzly bears, primarily caused by human activities such as forestry, oil and gas, and mining. The researchers recommend limiting human access to critical habitat sites and increasing education programs to mitigate the impact on the species.
A new map developed by the Wildlife Conservation Society predicts wolf attacks in Wisconsin and Minnesota based on road density, farm size, deer availability, and other factors. The maps identify high-risk townships with moderate to high risk of wolf attacks, which are clustered along the edge of the wolf population.
A study published in Conservation Biology found that non-lethal repellent methods, such as motion-activated devices with strobe lights and random noises, were effective in keeping predators away from deer carcasses. The methods outperformed traditional deterrents like electronic training collars.
Black bears in urban areas are spending less time hunting and more time eating human trash. The study found that these bears are becoming overweight and less active due to increased availability of food sources like garbage. Local ordinances can help mitigate conflicts by mandating bear-proof garbage containers.
A new study reveals a significant increase in Arctic summer melt season length, threatening polar bears' survival and global climate stability. The research uses radar data from European and American satellites to measure changes in Arctic sea ice thickness, shedding light on the impact of global warming.
A recent study by Wildlife Conservation Society researchers found that the reintroduction of wolves and grizzly bears in Yellowstone has led to ecosystem dysfunction. Female moose showed little reaction to predator sounds and smells, indicating a lack of ecological recovery.