Posted on January 24, 2014 by Bob Berwyn
A polar bear roams a coastal strand. Photo courtesy Susanne Miller, USFWS.
Studies show changing foraging behavior
By Summit Voice
FRISCO — A shared genetic heritage with brown bears may enable some polar bears to adapt as their icy Arctic hunting grounds shrink in the face of global warming.
As Arctic sea ice dwindles, polar bears have a limited amount of time to hunt their historically preferred prey — ringed seal pups — and must spend more time on land.
But polar bears in the western Hudson Bay region are using flexible foraging strategies while on land, such as prey-switching and eating a mixed diet of plants and animals, as they survive in their rapidly changing environment.
“There is little doubt that polar bears are very susceptible as global climate change continues to drastically alter the landscape of the northern polar regions,” said Robert Rockwell, a research associate at the American Museum of Natural History’s department of ornithology. “But we’re finding that they might be more resilient than is commonly thought.” Continue reading
Filed under: Arctic, biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: Arctic sea ice, climate change, endangered species, global warming, polar bears | 2 Comments »
Posted on September 20, 2013 by Bob Berwyn
A polar bear in the Arctic. PHOTO COURTESY USGS/SUSANNE MILLER.
Changing sea ice means shifting diet for top Arctic predators
By Summit Voice
FRISCO — The decline of Arctic sea ice is a huge threat to animals in the region, including polar bears and seals, and researchers are trying to learn how those changes will play out in the long run.
Even along the east coast of Greenland, where the sea ice may persist after it has vanished from other areas, the annual 1 percent decline in ice is affecting polar bears, according to an international team of researchers who studied polar bear diets.
After analyzing fatty tissues from 310 polar bears hunted by Greenland natives between 1984 and 2011, the scientists were able to detect subtle shifts in in their diet. Instead of relying primarily on ringed seals, residents of the high Arctic, the bears are increasingly eating subarctic harp and hooded seals. Continue reading
Filed under: Arctic, biodiversity, climate and weather, Environment, global warming, Greenland | Tagged: Arctic sea ice, global waming, greenland, Persistent organic pollutants, polar bears | Leave a comment »
Posted on May 20, 2013 by Bob Berwyn
A United States Fish & Wildlife Service polar bear biologist labels blood samples taken from a bear being examined.
Photo Credit: Karen Rode/USFWS.
New report says threats have increased since bears were listed in 2008
By Summit Voice
FRISCO — While nobody thinks the U.S. Fish and Wildlife Service can slow or stop global warming, wildlife conservation advocates say the agency must do more to try and save polar bears from extinction.
The great Arctic predators have become a poster child for the impacts of global warming, but five years after they were put on the Endangered Species List, the USFWS has not developed a recovery plan.
According to the Center for Biologicial Diversity, the federal agency also should be considering new scientific evidence that threats to polar bears have increased, warranting a change from “threatened” to “endangered” status. Continue reading
Filed under: biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: biodiversity, endangered species, endangered species act, global warming, polar bears, United States Fish & Wildlife Service | 1 Comment »
Posted on March 20, 2013 by Bob Berwyn
A detailed new study shows how declining sea ice affects polar bear migration. Photo courtesy USFWS.
Research may help explain declines in cub production and body condition
By Summit Voice
SUMMIT COUNTY — A 10-year study of polar bears around western Hudson Bay offers new clues to how the predators will cope with global warming.
The research, published in the British Ecological Society’s Journal of Animal Ecology, focused on how sea ice conditions drive polar bears’ annual migration on and off the ice.
Polar bears have adapted to the annual loss of sea ice by migrating onto land each summer. While there, they cannot hunt seals and must rely on fat reserves to see them through until the ice returns.
“The data suggest that in recent years, polar bears are arriving on shore earlier in the summer and leaving later in the autumn,” said Dr. Seth Cherry, of the University of Alberta. “These are precisely the kind of changes one would expect to see as a result of a warming climate and may help explain some other studies that are showing declines in body condition and cub production.” Continue reading
Filed under: biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: climate change, global warming, Hudson Bay polar bears, polar bears, Sea ice | Leave a comment »
Posted on March 2, 2013 by Bob Berwyn
Polar bears are threatened by global warming and qualify for protection under the Endangered Species Act. Photo courtesy Susanne Miller/USFWS.
Court rejects challenge by Alaska and trophy hunters
By Summit Voice
SUMMIT COUNTY — A federal appeals court has rebuffed Alaska’s efforts to weaken polar bear protection under the Endangered Species Act.
Explaining that global warming has already caused reductions in survival and recruitment rates in some regions, the D.C. Circuit Court of Appeals ruled that the U.S. Fish and Wildlife Service satisfied its duties under the law and adequately supported it decision to protect polar bears from extinction. Read the decision here.
The agency said the record makes it clear that federal biologists were aware of Alaska’s concerns and addressed them during the listing process. “We find … that under any reasonable reading of the Act, FWS committed no error in its response to the concerns raised by the State of Alaska,” the appeals court wrote in the March 1 ruling. Continue reading
Filed under: Arctic, biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: Alaska, Arctic sea ice, climate change, endangered species, global warming, polar bears | 1 Comment »
Posted on February 7, 2013 by Bob Berwyn
Are polar bears on the brink?
“It’s a fact that early sea ice break-up and late ice freeze-up and the overall reduction in ice pack are taking their toll.”
By Summit Voice
FRISCO — Despite reports of increases in isolated polar bear populations, the species as a whole is still imperiled by the rapid, steady rise in Arctic temperatures and shrinking areas of sea ice. Just one unexpected jump in Arctic warming trends could push the predators toward extinction, according to a new warning from a team of scientists led by University of Alberta polar bear researcher professor Andrew Derocher.
The new paper in the journal Conservation Letters is framed as a policy perspective, urging countries with polar bear populations to consider the long-term implications of climate change.
“It’s a fact that early sea ice break-up and late ice freeze-up and the overall reduction in ice pack are taking their toll,” Derocher said. “We want governments to be ready with conservation and management plans for polar bears when a worst case climate change scenario happens.” Continue reading
Filed under: Arctic, biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: Arctic, endangered species, global warming, polar bears, Sea ice, wildlife | 1 Comment »
Posted on December 8, 2012 by Bob Berwyn
Conservation groups are challenging Canada’s decision on polar bear conservation. Photo courtesy USFWS/Scott Schliebe.
Conservation status of polar bears in Canada challenged by petition to international trade group
By Summit Voice
FRISCO — Endangered polar bears are at the center of an an unusual dispute that will be heard by an environmental commission established under NAFTA.
The Commission for Environmental Cooperation announced late last t month that it will consider a petition challenging Canada’s decision to list polar bears as a species of special concern instead of listing them as threatened or endangered. The commission announced the petition filed by the Center for Biological Diversity provides sufficient documentation of Canada’s violations of its own laws to warrant an official response from the country’s government. Continue reading
Filed under: biodiversity, endangered species, Environment | Tagged: biodiversity, Canada, Center for Biological Diversity, endangered species, NAFTA, polar bears, wildlife | Leave a comment »
Posted on May 24, 2012 by Bob Berwyn
Scientists try to assess potential impact of shrinking sea ice
Some Polar bears in the Arctic can swim in excess of 200 miles, according to USGS research.
Scientists track Polar bears with by attaching GPS equipped collars to a sample population. These collars transmit data that help develop maps like this one that shows a swim of nearly 220 miles long. MAP COURTESY USGS.
By Bob Berwyn
SUMMIT COUNTY — Given the steady decline of sea ice in the Arctic and the status of polar bears as threatened under the Endangered Species Act, biologists are trying to understand how the top-level predators might respond to those changing conditions.
It’s important because some of the most recent studies link declining sea ice with dropping polar bear survival and reproduction rates in the Southern Beaufort Sea and around Hudson Bay.
“With the sea ice retreating earlier and coming back later, there’s less time for them to hunt in the spring, when put on their fat,” said Alaska-based U.S. Geological Survey researcher Anthony Pagano. “They end up in poor body condition,” Pagano said, adding that some of the studies suggest a downward trend in average body weight. Continue reading
Filed under: biodiversity, climate and weather, endangered species, Environment, global warming | Tagged: Arctic sea ice, Beaufort Sea, endangered species, global warming, polar bears, polar bears swimming, US Geological Survey | Leave a comment »
Posted on April 6, 2012 by Bob Berwyn
Polar bears in the Arctic. PHOTO COURTESY USGS.
Long-running investigation appears to be heading nowhere
By Summit Violce
SUMMIT COUNTY — Federal investigators last week continued to pursue what looks more and more like a witch hunt against scientists who are researching Arctic ecosystems by interviewing new witnesses.
The investigation, which has changed course and shifted shape several times since 2010, is now looking at data from a long-running bowhead whale survey program, but the main effect has been to leave some federal scientists fearful about potential career risks associated with overseeing Arctic Research projects, according to a whistle-blower protection and watchdog group. Continue reading
Filed under: biodiversity, endangered species, Environment | Tagged: Arctic research, Charles Monnett, polar bears | Leave a comment »
Posted on March 30, 2012 by Bob Berwyn
Polar bears catch a bit of break, as sampling in one area shows a drop in levels of toxic PCBs. PHOTO COURTESY USGS.
Some good news for a species under pressure
By Summit Voice
SUMMIT COUNTY — Norwegian researchers say efforts to reduce the use of toxic PCBs in various products is paying off for polar bears in Svalbard.
Recent tests found that blood levels of PCBs and related contaminants in polar bear cubs appear to have dropped by as much as 59 per cent between 1998 and 2008. At the same time, levels of these contaminants in their mothers were as much as 55 per cent lower over the same period.
The studies were conducted by the Norwegian University of Science and Technology, who looked at blood samples from mothers and cubs that were collected in 1997 and 1998 and 2008. All told, she had samples from 26 mother bears and 38 cubs from the different time periods. Continue reading
Filed under: biodiversity, endangered species, Environment | Tagged: biodiversity, PCBs, Persistent organic pollutants, polar bears, Svalbard | Leave a comment »