Polar bear cub is raised by hand
A baby polar bear cub is being raised by human carers in Denmark after its mother failed to produce any milk.
Siku - still blind and deaf - has to be bottle-fed by staff at the Scandinavian Wildlife Park near Kolind.
Zoo director Frank Vigh-Larsen said: "Our polar bear female Ilka had a cub, but after two days we decided to immobilise Ilka, because the cub was constantly screaming and being very unsettled.
"Ilka had absolutely no milk, so instead of leaving the cub to die we decided to try to bottle feed it.
"It is now 30 days old, and weighs 3.2 grams, 2.4 grams more than at birth, and he is thriving."
The polar bears in Scandinavian Wildlife Park are part of a global breeding program for captive polar bears.
Mr Vigh-Larsen added: "We are convinced that it will be possible for Siku to become a normal functioning polar bear within a few years, so he can live together with the other polar bears in the park."
See video here ...
Showing posts with label polar bear. Show all posts
Showing posts with label polar bear. Show all posts
Monday, December 26, 2011
Friday, December 9, 2011
Polar bear 'cannibalism' pictured
By Jonathan Amos
Science correspondent, BBC News, San Francisco
It is an image that is sure to shock many people.
An adult polar bear is seen dragging the body of a cub that it has just killed across the Arctic sea ice.
Polar bears normally hunt seals but if these are not available, the big predators will seek out other sources of food - even their own kind.
The picture was taken by environmental photojournalist Jenny Ross in Olgastretet, a stretch of water in the Svalbard archipelago.
"This type of intraspecific predation has always occurred to some extent," she told BBC News.
"However, there are increasing numbers of observations of it occurring, particularly on land where polar bears are trapped ashore, completely food-deprived for extended periods of time due to the loss of sea ice as a result of climate change."
The journalist was relating the story behind her pictures here at the 2011 American Geophysical Union (AGU) Fall Meeting, the largest annual gathering of Earth scientists.
A paper describing the kill event in July 2010 has just been published in the journal Arctic. It is co-authored with Dr Ian Stirling, a polar bear biologist from Environment Canada.
Ross had approached the adult in a boat. She could see through her telephoto lens that the animal had a meal, but it was only when she got up close that she realised it was a juvenile bear.
The kill method used by the adult was exactly the same as polar bears use on seals - sharp bites to the head.
Read more here ...
Science correspondent, BBC News, San Francisco
It is an image that is sure to shock many people.
An adult polar bear is seen dragging the body of a cub that it has just killed across the Arctic sea ice.
Polar bears normally hunt seals but if these are not available, the big predators will seek out other sources of food - even their own kind.
The picture was taken by environmental photojournalist Jenny Ross in Olgastretet, a stretch of water in the Svalbard archipelago.
"This type of intraspecific predation has always occurred to some extent," she told BBC News.
"However, there are increasing numbers of observations of it occurring, particularly on land where polar bears are trapped ashore, completely food-deprived for extended periods of time due to the loss of sea ice as a result of climate change."
The journalist was relating the story behind her pictures here at the 2011 American Geophysical Union (AGU) Fall Meeting, the largest annual gathering of Earth scientists.
A paper describing the kill event in July 2010 has just been published in the journal Arctic. It is co-authored with Dr Ian Stirling, a polar bear biologist from Environment Canada.
Ross had approached the adult in a boat. She could see through her telephoto lens that the animal had a meal, but it was only when she got up close that she realised it was a juvenile bear.
The kill method used by the adult was exactly the same as polar bears use on seals - sharp bites to the head.
Read more here ...
Thursday, October 27, 2011
Urgent need for action to save polar bears
Bears' habitats are literally melting away...October 2011: A dramatic reduction in polar-bear habitats in the next ten to 50 years has been predicted. The study by IUCN (International Union for Conservation of Nature) warns this is due largely to global warming.
The IUCN Red List of Threatened Species assesses polar bears as Vulnerable, with trends that suggest the population is decreasing. Polar bears rely almost entirely on the marine sea ice environment for their survival, so much so that large scale changes in their habitat will have a devastating impact on the population.
'They will disappear from many areas they are found today'‘Now is the time to act in order to save the waning polar bear population,' says Dag Vongraven, who heads up IUCN's polar bear specialist group, the Norwegian Polar Institute (NPI). ‘If we fail to make a stand to save this species we risk having the population become severely decimated, and quite certainly they will have disappeared from many areas where they're found today.'
Climate change poses the most substantial threat to polar bear habitats. Recent trends for sea ice extent and thickness predict dramatic reductions over coming years- declines of roughly ten to 50 per cent of annual sea ice are predicted by 2100. A recent study by the NPI suggests that summer sea ice in the Polar Basin might be gone in a decade, not 50 to 100 years as most models have projected in the past. The long-term trends reveal substantial global reductions of the extent of ice coverage in the Arctic and the length of time ice when is present each year.
There must be strong commitments to cut greenhouse gases – now‘Climate change will be one of the major drivers of species extinctions in the 21st century,' says Simon Stuart, chairman of IUCN's Species Survival Commission. ‘In order to slow the pace the adverse effects of climate change are having on species around the world, we must work to reduce use of energy from fossil fuels and ensure that our leaders make and adhere to strong commitments to cut greenhouse gas emissions now.'
Polar bears live throughout the ice-covered waters of Canada, Greenland, Norway, the Russian Federation and Alaska. Their range is limited by the southern extent of sea ice. Polar bears that have continuous access to sea ice can hunt throughout the year, but in areas where the sea ice melts completely each summer, the bears are forced to spend several months on land fasting on stored fat reserves until freeze-up.
Other population stress factors that also impact the species survival include toxic contaminants, shipping, recreational viewing and oil and gas exploration. The polar bear is unique among species protected under the Endangered Species Act because it is the first to be designated as threatened due to global warming.
http://www.wildlifeextra.com/go/news/polar-bear-decline.html
The IUCN Red List of Threatened Species assesses polar bears as Vulnerable, with trends that suggest the population is decreasing. Polar bears rely almost entirely on the marine sea ice environment for their survival, so much so that large scale changes in their habitat will have a devastating impact on the population.
'They will disappear from many areas they are found today'‘Now is the time to act in order to save the waning polar bear population,' says Dag Vongraven, who heads up IUCN's polar bear specialist group, the Norwegian Polar Institute (NPI). ‘If we fail to make a stand to save this species we risk having the population become severely decimated, and quite certainly they will have disappeared from many areas where they're found today.'
Climate change poses the most substantial threat to polar bear habitats. Recent trends for sea ice extent and thickness predict dramatic reductions over coming years- declines of roughly ten to 50 per cent of annual sea ice are predicted by 2100. A recent study by the NPI suggests that summer sea ice in the Polar Basin might be gone in a decade, not 50 to 100 years as most models have projected in the past. The long-term trends reveal substantial global reductions of the extent of ice coverage in the Arctic and the length of time ice when is present each year.
There must be strong commitments to cut greenhouse gases – now‘Climate change will be one of the major drivers of species extinctions in the 21st century,' says Simon Stuart, chairman of IUCN's Species Survival Commission. ‘In order to slow the pace the adverse effects of climate change are having on species around the world, we must work to reduce use of energy from fossil fuels and ensure that our leaders make and adhere to strong commitments to cut greenhouse gas emissions now.'
Polar bears live throughout the ice-covered waters of Canada, Greenland, Norway, the Russian Federation and Alaska. Their range is limited by the southern extent of sea ice. Polar bears that have continuous access to sea ice can hunt throughout the year, but in areas where the sea ice melts completely each summer, the bears are forced to spend several months on land fasting on stored fat reserves until freeze-up.
Other population stress factors that also impact the species survival include toxic contaminants, shipping, recreational viewing and oil and gas exploration. The polar bear is unique among species protected under the Endangered Species Act because it is the first to be designated as threatened due to global warming.
http://www.wildlifeextra.com/go/news/polar-bear-decline.html
Friday, August 5, 2011
Polar bear kills British tourist in Norway attack
A tourist thought to belong to the British Schools Exploring Society has been killed by a polar bear in the Arctic archipelago of Svalbard in Norway. Four others belonging to the same party and believed to be British have been 'severely injured' in the bear attack.
The attack happened this morning and the victims were rushed to Svalbard capital Lonyearbyen, about 25 miles away.
The four survivors were said to be 'severely injured' and were set to be flown in air ambulances to University Hospital in Tromso.
The British Schools Exploring Society, based in Kensington, London, could not comment today but it was believed that a statement may be made later.
The Svalbard Governor issued a warning earlier this year about polar bears after several were seen close to Longyearbyen.
Svalbard-based restaurant manager Sandra Swresser told The Guardian website: 'It's very sad. We have had attacks before. It happened a year ago when a Norwegian man was attacked. As it was early in the morning I can only suppose the bear attacked them because it was looking for food.'
Another Svalbard resident, Liv Rose Flygel, 55, told The Guardian: 'It's not been the first time. Last summer a man was attacked by a polar bear and there have also been attacks on a man from Austria and a girl. Only the man in the attack last summer survived. He was taken in the mouth of the bear and his friend ran after it and shot it.
'The problem is, when the ice goes, the bears lose their way and cannot catch food. People don't really how dangerous they are. One came down to the sea recently and people were running down to take pictures.'
Read more: http://www.metro.co.uk/news/871484-polar-bear-kills-british-tourist-in-norway-attack#ixzz1UA021vAL
The attack happened this morning and the victims were rushed to Svalbard capital Lonyearbyen, about 25 miles away.
The four survivors were said to be 'severely injured' and were set to be flown in air ambulances to University Hospital in Tromso.
The British Schools Exploring Society, based in Kensington, London, could not comment today but it was believed that a statement may be made later.
The Svalbard Governor issued a warning earlier this year about polar bears after several were seen close to Longyearbyen.
Svalbard-based restaurant manager Sandra Swresser told The Guardian website: 'It's very sad. We have had attacks before. It happened a year ago when a Norwegian man was attacked. As it was early in the morning I can only suppose the bear attacked them because it was looking for food.'
Another Svalbard resident, Liv Rose Flygel, 55, told The Guardian: 'It's not been the first time. Last summer a man was attacked by a polar bear and there have also been attacks on a man from Austria and a girl. Only the man in the attack last summer survived. He was taken in the mouth of the bear and his friend ran after it and shot it.
'The problem is, when the ice goes, the bears lose their way and cannot catch food. People don't really how dangerous they are. One came down to the sea recently and people were running down to take pictures.'
Read more: http://www.metro.co.uk/news/871484-polar-bear-kills-british-tourist-in-norway-attack#ixzz1UA021vAL
Sunday, July 10, 2011
Polar bears traced back to Britain
All polar bears originate from a single ancestor which lived in Britain or Ireland about 50,000 years ago, according to DNA study by scientists. New evidence from fossils found in Irish caves shows that modern polar bars evolved from a single female brown bear at the peak of the last ice age.
Despite the significant differences between polar bears, which are expert swimmers, and brown bears, which are better climbers, the species have often come into contact over the past 100,000 years during periods of unusually hot or cold weather.
A genetic marker carried by every polar bear alive today proves that they all descend from the same female brown bear, who bred with a polar bear to create hybrid offspring.
It had been assumed that this took place in Alaska 14,000 years ago, but now analysis of 242 brown bear and polar bear DNA samples from the past 120,000 years show the hybridisation of the two species occurred much earlier.
Fossils found in Irish caves show that polar bears in fact began carrying the DNA of the female brown bear between 20,000 and 50,000 years ago, before brown bears disappeared from the British Isles.
The study, led by Dr Beth Shapiro of Penn State University in the USA and Prof Daniel Bradley of Trinity College Dublin, was published in the journal Current Biology.
Dr Shapiro said: “Previous research has indicated that the brown bear contributed genetic material to the polar bear's mitochondrial lineage – the DNA that is passed exclusively from mothers to offspring.
“But, until now, it was unclear just when modern polar bears acquired their mitochondrial genome in its present form."
By Nick Collins, Science Correspondent
http://www.telegraph.co.uk/earth/wildlife/8622987/Polar-bears-traced-back-to-Britain.html
Despite the significant differences between polar bears, which are expert swimmers, and brown bears, which are better climbers, the species have often come into contact over the past 100,000 years during periods of unusually hot or cold weather.
A genetic marker carried by every polar bear alive today proves that they all descend from the same female brown bear, who bred with a polar bear to create hybrid offspring.
It had been assumed that this took place in Alaska 14,000 years ago, but now analysis of 242 brown bear and polar bear DNA samples from the past 120,000 years show the hybridisation of the two species occurred much earlier.
Fossils found in Irish caves show that polar bears in fact began carrying the DNA of the female brown bear between 20,000 and 50,000 years ago, before brown bears disappeared from the British Isles.
The study, led by Dr Beth Shapiro of Penn State University in the USA and Prof Daniel Bradley of Trinity College Dublin, was published in the journal Current Biology.
Dr Shapiro said: “Previous research has indicated that the brown bear contributed genetic material to the polar bear's mitochondrial lineage – the DNA that is passed exclusively from mothers to offspring.
“But, until now, it was unclear just when modern polar bears acquired their mitochondrial genome in its present form."
By Nick Collins, Science Correspondent
http://www.telegraph.co.uk/earth/wildlife/8622987/Polar-bears-traced-back-to-Britain.html
Friday, April 15, 2011
Polar bear Mercedes put to sleep
15 April 201
Mercedes the polar bear has been "put to sleep" after a "recent rapid deterioration in her welfare", the Royal Zoological Society of Scotland (RZSS) has announced.
The 30-year-old female bear was moved from Edinburgh Zoo to a new, larger enclosure at the Highland Wildlife Park near Aviemore two years ago.
She had been suffering severe arthritis which was treated with painkillers.
The RZSS said it was "with great sadness" that it announced the death.
Mercedes was captured after being rescued from being shot in Canada in 1984 and added to the animal collection at Edinburgh Zoo.
She was relocated to the park at Kincraig in 2009.
During her 25 years in Edinburgh, Mercedes reared two cubs, both sired by her partner Barney, who was born at Whipsnade Zoo.
After the death of Barney in 1996, Mercedes lived by herself at Edinburgh Zoo until she moved to the Highland Wildlife Park in 2009.
A two-year-old male polar bear called Walker was introduced to Mercedes's enclosure in November 2010.
However, an ageing Mercedes was not happy to play with a young cub.
Rapid downturn
A statement from the RZSS, which runs Edinburgh Zoo and the Highland Wildlife Park, said: "More recently we noted a marked and rapid downturn in her behaviour and her demeanour, and she appeared to be ageing very rapidly and possibly showing signs of senility.
"We had been keeping her separate from the male bear so as to avoid any possibility of him causing her to move more than she wanted to.
"Recently, all of the individuals responsible for her care sadly concluded that our only remaining option was to put her to sleep on age and health grounds."
Simon Girling, RZSS head of veterinary services, said: "We have been monitoring Mercedes's condition for some time now and have tried a number of different therapies for her advanced arthritis, which we were having some success with.
"However, even on medication, Mercedes has now taken a significant turn for the worse in terms of her mobility and is also showing signs of mental confusion.
"This deterioration in her welfare has prompted us to step in and humanely euthanase her."
http://www.bbc.co.uk/news/uk-scotland-highlands-islands-13094316
Mercedes the polar bear has been "put to sleep" after a "recent rapid deterioration in her welfare", the Royal Zoological Society of Scotland (RZSS) has announced.
The 30-year-old female bear was moved from Edinburgh Zoo to a new, larger enclosure at the Highland Wildlife Park near Aviemore two years ago.
She had been suffering severe arthritis which was treated with painkillers.
The RZSS said it was "with great sadness" that it announced the death.
Mercedes was captured after being rescued from being shot in Canada in 1984 and added to the animal collection at Edinburgh Zoo.
She was relocated to the park at Kincraig in 2009.
During her 25 years in Edinburgh, Mercedes reared two cubs, both sired by her partner Barney, who was born at Whipsnade Zoo.
After the death of Barney in 1996, Mercedes lived by herself at Edinburgh Zoo until she moved to the Highland Wildlife Park in 2009.
A two-year-old male polar bear called Walker was introduced to Mercedes's enclosure in November 2010.
However, an ageing Mercedes was not happy to play with a young cub.
Rapid downturn
A statement from the RZSS, which runs Edinburgh Zoo and the Highland Wildlife Park, said: "More recently we noted a marked and rapid downturn in her behaviour and her demeanour, and she appeared to be ageing very rapidly and possibly showing signs of senility.
"We had been keeping her separate from the male bear so as to avoid any possibility of him causing her to move more than she wanted to.
"Recently, all of the individuals responsible for her care sadly concluded that our only remaining option was to put her to sleep on age and health grounds."
Simon Girling, RZSS head of veterinary services, said: "We have been monitoring Mercedes's condition for some time now and have tried a number of different therapies for her advanced arthritis, which we were having some success with.
"However, even on medication, Mercedes has now taken a significant turn for the worse in terms of her mobility and is also showing signs of mental confusion.
"This deterioration in her welfare has prompted us to step in and humanely euthanase her."
http://www.bbc.co.uk/news/uk-scotland-highlands-islands-13094316
Sunday, March 20, 2011
Knut is dead: Beloved polar bear collapses and dies in front of 600 visitors
By Daily Mail Reporter
Last updated at 6:28 AM on 20th March 2011
Last updated at 6:28 AM on 20th March 2011
Knut, the world-famous polar bear, collapsed and died in front of 600 visitors at Berlin Zoo this afternoon.
The bear rose to stardom when he was hand-raised by zoo keepers after being rejected by his mother at birth.
Bear keeper Heiner Kloes from the zoo said the four-year-old was alone in his compound. He says the cause is not yet clear.
'He was by himself in his compound, he was in the water, and then he was dead,' said Mr Kloes. ' He was not sick, we don't know why he died.'
A post mortem will be conducted on Monday to try pinpoint his cause of death, he said.
Berlin Mayor Klaus Wowereit called Knut's death 'awful'.
'We all held him so dearly,' he told daily newspaper B.Z. 'He was the star of the Berlin zoo.'
The polar bear rose to global fame after he was rejected by his mother when he was born in captivity on December 5, 2006. The fluffy cub was shown to the public 15 weeks later, and attendance at the zoo has roughly doubled since, officials said.
The resulting 'Knutmania' led to a 2007 Vanity Fair cover with actor Leonardo DiCaprio shot by famed photographer Annie Leibovitz.
Though the zoo has never released exact numbers, Knut merchandise including postcards, key chains, candy and stuffed Knuts have brought in hundreds of thousands of euros.
Although Knut was the first polar bear to be born and survive at Berlin Zoo in more than 30 years, his tragic young life was blighted by tragedy from the start.
Both he and his twin were rejected by their mother at birth and his unnamed brother died four days later.
But Knut amazed medical staff at the zoo by clinging to life. After spending his first 44 days in an incubator, he was put in the care of zoo keeper Thomas Dörflein, who began raising the infant with round-the clock care.
News of the cub's miraculous survival was picked up by the world's media and the young cub became the zoo's top attraction.
But tragedy struck again before Knut's second birthday in 2008, when Mr Dorflein died of a sudden heart attack at the age of 44.
Observers noted that the bear appeared to suffer from depression in the weeks after his beloved keeper and constant companion died.
Experts had earlier warned that the Knut was developing into a 'psychopath' who was too dependent on human contact.
In 2009 Knut was the subject of a bitter custody battle between two zoos. Neumuenster Zoo had loaned Berlin Zoo Knut’s father Lars in 1999 on the condition that the first-born cub from his union with mother Tosca would belong to Neumuenster.
And last year Knut's cousin died after a mystery virus spread through the zoo's bear enclosure.
http://www.dailymail.co.uk/news/article-1367921/Knut-dead-German-polar-bear-dies-600-visitors-Berlin-Zoo.html?ITO=1490
Wednesday, February 9, 2011
Polar scare! Children swim inches from monster bears (which would be a worry if you don't notice the glass barrier)
By Daily Mail Reporter
Last updated at 5:27 PM on 8th February 2011
It's a heart-in-the-mouth moment that would have most parents running for help.
The massive carnivores loom menacingly over their bite-size pool companions in these remarkable pictures.
But there's more to the scenario than meets the eye, in fact the children are separated from certain death by 10-inch thick plexiglas.
Both children and bears are actually very safely taking part in an amazing initiative by the owners of Cochrane Polar Bear Habitat, in Ontario, Canada, in a attempt to promote awareness about the amazing animals.
The sanctuary takes in only bears rescued from the wild and through letting visitors get so close they hope to foster understanding and reduce hunting in the wild.
Former director at the centre and keen photographer Gerry Robichaud took the amazing photographs of the moment bear meets man in the safety of the tank.
He said: 'You do get some very surprised reactions from visitors when they first see the bears and the children in the pool.
'When you're in the water and up by the glass next to these animals it barely seems like there is anything protecting you, when in fact there's a 10-inch think barrier.
'We get various reactions from the children, some of them can't wait to get in the pool and others really don't want to. It's the adults you have to watch out for, some of them jump in still with all their clothes on.
'The two bears in the pictures are actually females, Aurora and Nikita, both who we took in as rescue animals.
'They came to us a cubs after a tribe told us about them because their mother had been shot by a hunter near Winisk, near the Hudson Bay in the far north.'
Gerry, 59, said the aim was to give the bears as much stimulation as possible in their 100m by 200m enclosure.
He said: 'I have been in the water myself when the public have not been here and actually realised one of the bears was stalking me, she was hiding and keeping very low in the water. It was quite an odd feeling.
'I have lived in the far north with the people up there myself and documented their lives, it's a different world up there.'
More: http://www.dailymail.co.uk/news/article-1354786/Children-swim-inches-monster-polar-bears.html
Last updated at 5:27 PM on 8th February 2011
It's a heart-in-the-mouth moment that would have most parents running for help.
The massive carnivores loom menacingly over their bite-size pool companions in these remarkable pictures.
But there's more to the scenario than meets the eye, in fact the children are separated from certain death by 10-inch thick plexiglas.
 |
| Within touching distance: Children swim incredibly close to two enormous polar bears at a rescue centre with a difference in Ontario, Canada |
The sanctuary takes in only bears rescued from the wild and through letting visitors get so close they hope to foster understanding and reduce hunting in the wild.
Former director at the centre and keen photographer Gerry Robichaud took the amazing photographs of the moment bear meets man in the safety of the tank.
He said: 'You do get some very surprised reactions from visitors when they first see the bears and the children in the pool.
'When you're in the water and up by the glass next to these animals it barely seems like there is anything protecting you, when in fact there's a 10-inch think barrier.
'We get various reactions from the children, some of them can't wait to get in the pool and others really don't want to. It's the adults you have to watch out for, some of them jump in still with all their clothes on.
'The two bears in the pictures are actually females, Aurora and Nikita, both who we took in as rescue animals.
'They came to us a cubs after a tribe told us about them because their mother had been shot by a hunter near Winisk, near the Hudson Bay in the far north.'
Gerry, 59, said the aim was to give the bears as much stimulation as possible in their 100m by 200m enclosure.
He said: 'I have been in the water myself when the public have not been here and actually realised one of the bears was stalking me, she was hiding and keeping very low in the water. It was quite an odd feeling.
'I have lived in the far north with the people up there myself and documented their lives, it's a different world up there.'
More: http://www.dailymail.co.uk/news/article-1354786/Children-swim-inches-monster-polar-bears.html
Tuesday, January 25, 2011
Polar bear's epic nine day swim in search of sea ice
By Ella Davies
Earth News reporter
A polar bear swam continuously for over nine days, covering 687km (426 miles), a new study has revealed.
Scientists studying bears around the Beaufort sea, north of Alaska, claim this endurance feat could be a result of climate change.
Polar bears are known to swim between land and sea ice floes to hunt seals.
But the researchers say that increased sea ice melts push polar bears to swim greater distances, risking their own health and future generations.
In their findings, published in Polar Biology, researchers from the US Geological Survey reveal the first evidence of long distance swimming by polar bears (Ursus maritimus).
"This bear swam continuously for 232 hours and 687 km and through waters that were 2-6 degrees C," says research zoologist George M. Durner.
"We are in awe that an animal that spends most of its time on the surface of sea ice could swim constantly for so long in water so cold. It is truly an amazing feat."
Although bears have been observed in open water in the past, this is the first time one's entire journey has been followed.
By fitting a GPS collar to a female bear, researchers were able to accurately plot its movements for two months as it sought out hunting grounds.
The scientists were able to determine when the bear was in the water by the collar data and a temperature logger implanted beneath the bear's skin.
The study shows that this epic journey came at a very high cost to the bear.
"This individual lost 22% of her body fat in two months and her yearling cub," says Mr Durner.
"It was simply more energetically costly for the yearling than the adult to make this long distance swim," he explains.
Mr Durner tells the BBC that conditions in the Beaufort sea have become increasingly difficult for polar bears.
"In prior decades, before 1995, low-concentration sea ice persisted during summers over the continental shelf in the Beaufort Sea."
"This means that the distances, and costs to bears, to swim between isolated ice floes or between sea ice and land was relatively small."
"The extensive summer melt that appears to be typical now in the Beaufort Sea has likely increased the cost of swimming by polar bears."
Polar bears live within the Arctic circle and eat a calorie-rich diet of ringed seals (Pusa hispida) to survive the frozen conditions.
The bears hunt their prey on frozen sea ice: a habitat that changes according to temperature.
"This dependency on sea ice potentially makes polar bears one of the most at-risk large mammals to climate change," says Mr Durner.
The IUCN red list identifies polar bears as a vulnerable species, citing global climate change as a "substantial threat" to their habitat.
http://news.bbc.co.uk/earth/hi/earth_news/newsid_9369000/9369317.stm
(Submitted by Liz R)
Polar bear's epic nine day swim in search of sea ice
By Ella Davies
Earth News reporter
A polar bear swam continuously for over nine days, covering 687km (426 miles), a new study has revealed.
Scientists studying bears around the Beaufort sea, north of Alaska, claim this endurance feat could be a result of climate change.
Polar bears are known to swim between land and sea ice floes to hunt seals.
But the researchers say that increased sea ice melts push polar bears to swim greater distances, risking their own health and future generations.
In their findings, published in Polar Biology, researchers from the US Geological Survey reveal the first evidence of long distance swimming by polar bears (Ursus maritimus).
"This bear swam continuously for 232 hours and 687 km and through waters that were 2-6 degrees C," says research zoologist George M. Durner.
"We are in awe that an animal that spends most of its time on the surface of sea ice could swim constantly for so long in water so cold. It is truly an amazing feat."
Although bears have been observed in open water in the past, this is the first time one's entire journey has been followed.
By fitting a GPS collar to a female bear, researchers were able to accurately plot its movements for two months as it sought out hunting grounds.
The scientists were able to determine when the bear was in the water by the collar data and a temperature logger implanted beneath the bear's skin.
The study shows that this epic journey came at a very high cost to the bear.
"This individual lost 22% of her body fat in two months and her yearling cub," says Mr Durner.
"It was simply more energetically costly for the yearling than the adult to make this long distance swim," he explains.
Mr Durner tells the BBC that conditions in the Beaufort sea have become increasingly difficult for polar bears.
"In prior decades, before 1995, low-concentration sea ice persisted during summers over the continental shelf in the Beaufort Sea."
"This means that the distances, and costs to bears, to swim between isolated ice floes or between sea ice and land was relatively small."
"The extensive summer melt that appears to be typical now in the Beaufort Sea has likely increased the cost of swimming by polar bears."
Polar bears live within the Arctic circle and eat a calorie-rich diet of ringed seals (Pusa hispida) to survive the frozen conditions.
The bears hunt their prey on frozen sea ice: a habitat that changes according to temperature.
"This dependency on sea ice potentially makes polar bears one of the most at-risk large mammals to climate change," says Mr Durner.
The IUCN red list identifies polar bears as a vulnerable species, citing global climate change as a "substantial threat" to their habitat.
http://news.bbc.co.uk/earth/hi/earth_news/newsid_9369000/9369317.stm
(Submitted by Liz R)
Thursday, December 23, 2010
Polar bears not endangered, US confirms (via Dawn Holloway)
Environmental campaigners in the US have lost a battle to have the polar bear listed as an "endangered" species.
The US department of the interior has upheld a decision to classify the bear as "threatened" - a status that gives them less protection under the law.
The government said it did not find that polar bears were on the brink of extinction, needed to qualify for the status of "endangered".
Environmental campaigners have said they will challenge the decision.
'Anti-science decision'
Under the Endangered Species Act, the status of "endangered" requires the government to assess the impact of greenhouse gases on the bears' Arctic homelands.
When the government is considering permits for oil development in northern Alaska, it must include greenhouse gas emissions in its decision.
When the polar bear was listed as "threatened" by the administration of former US President George W Bush, officials invoked a special rule saying the Endangered Species Act could not be used to regulate greenhouse gas emissions.
So an "endangered" listing is a more powerful tool for limiting industrial activity that causes greenhouse gases.
The Centre for Biological Diversity - one of the groups trying to get the polar bear listed as "endangered" - said the ruling showed that the administration of US President Barack Obama was continuing to defend Bush-era "anti-science decisions".
It says polar bears face an 80% chance of extinction within 40 years and it will continue to challenge the US government in court.
By Rajesh Mirchandani
BBC News
http://www.bbc.co.uk/news/world-us-canada-12065257
The US department of the interior has upheld a decision to classify the bear as "threatened" - a status that gives them less protection under the law.
The government said it did not find that polar bears were on the brink of extinction, needed to qualify for the status of "endangered".
Environmental campaigners have said they will challenge the decision.
'Anti-science decision'
Under the Endangered Species Act, the status of "endangered" requires the government to assess the impact of greenhouse gases on the bears' Arctic homelands.
When the government is considering permits for oil development in northern Alaska, it must include greenhouse gas emissions in its decision.
When the polar bear was listed as "threatened" by the administration of former US President George W Bush, officials invoked a special rule saying the Endangered Species Act could not be used to regulate greenhouse gas emissions.
So an "endangered" listing is a more powerful tool for limiting industrial activity that causes greenhouse gases.
The Centre for Biological Diversity - one of the groups trying to get the polar bear listed as "endangered" - said the ruling showed that the administration of US President Barack Obama was continuing to defend Bush-era "anti-science decisions".
It says polar bears face an 80% chance of extinction within 40 years and it will continue to challenge the US government in court.
By Rajesh Mirchandani
BBC News
http://www.bbc.co.uk/news/world-us-canada-12065257
Polar bears not endangered, US confirms (via Dawn Holloway)
Environmental campaigners in the US have lost a battle to have the polar bear listed as an "endangered" species.
The US department of the interior has upheld a decision to classify the bear as "threatened" - a status that gives them less protection under the law.
The government said it did not find that polar bears were on the brink of extinction, needed to qualify for the status of "endangered".
Environmental campaigners have said they will challenge the decision.
'Anti-science decision'
Under the Endangered Species Act, the status of "endangered" requires the government to assess the impact of greenhouse gases on the bears' Arctic homelands.
When the government is considering permits for oil development in northern Alaska, it must include greenhouse gas emissions in its decision.
When the polar bear was listed as "threatened" by the administration of former US President George W Bush, officials invoked a special rule saying the Endangered Species Act could not be used to regulate greenhouse gas emissions.
So an "endangered" listing is a more powerful tool for limiting industrial activity that causes greenhouse gases.
The Centre for Biological Diversity - one of the groups trying to get the polar bear listed as "endangered" - said the ruling showed that the administration of US President Barack Obama was continuing to defend Bush-era "anti-science decisions".
It says polar bears face an 80% chance of extinction within 40 years and it will continue to challenge the US government in court.
By Rajesh Mirchandani
BBC News
http://www.bbc.co.uk/news/world-us-canada-12065257
The US department of the interior has upheld a decision to classify the bear as "threatened" - a status that gives them less protection under the law.
The government said it did not find that polar bears were on the brink of extinction, needed to qualify for the status of "endangered".
Environmental campaigners have said they will challenge the decision.
'Anti-science decision'
Under the Endangered Species Act, the status of "endangered" requires the government to assess the impact of greenhouse gases on the bears' Arctic homelands.
When the government is considering permits for oil development in northern Alaska, it must include greenhouse gas emissions in its decision.
When the polar bear was listed as "threatened" by the administration of former US President George W Bush, officials invoked a special rule saying the Endangered Species Act could not be used to regulate greenhouse gas emissions.
So an "endangered" listing is a more powerful tool for limiting industrial activity that causes greenhouse gases.
The Centre for Biological Diversity - one of the groups trying to get the polar bear listed as "endangered" - said the ruling showed that the administration of US President Barack Obama was continuing to defend Bush-era "anti-science decisions".
It says polar bears face an 80% chance of extinction within 40 years and it will continue to challenge the US government in court.
By Rajesh Mirchandani
BBC News
http://www.bbc.co.uk/news/world-us-canada-12065257
Wednesday, November 24, 2010
Study sees polar bears losing out to grizzlies
(Reuters) - Polar bears are likely to lose out to grizzly bears in fierce competition for food as climate change drives the two species closer together into shared habitat, biologists concluded in a study released on Tuesday.
The research was based on 3-D computer modeling that compared the skull and jaw strength of the two bruins and found polar bears ill-suited to the tougher chewing demands posed by the largely vegetarian diet of their grizzly cousins.
The study, funded by the National Science Foundation, was conducted by evolutionary biologists at the University of California, Los Angeles, and published in an online journal of the Public Library of Science.
The findings add to mounting signs of threats to polar bears from global warming that scientists attribute to excessive levels of carbon dioxide and other heat-trapping "greenhouse gases" emitted by human activities, such as the burning of fossil fuels.
"This is one additional piece of evidence that things look pretty bleak for the polar bear, if current trends continue," said Graham Slater, the lead author of the research.
Polar bears already are losing habitat as rising Arctic temperatures diminish the sea ice they depend on to hunt for seals. As the ice continues to shrink, polar bears will be forced to seek additional food sources.
"To people who say polar bears can just change their diet, we are saying ... they will have to, but it probably will not be sufficient for them, especially if they are co-existing with grizzly bears," said Blair Van Valkenburgh, senior author of the paper.
Grizzlies, a subspecies of brown bears, have begun moving north in Canada as their natural habitat grows milder, while polar bears are being pushed farther south by melting ice, putting the two species together in territory best suited to the grizzly.
"These two species are already starting to come into contact," Slater said. And in the escalating competition for the plant life that makes up the bulk of the grizzly's diet, the polar bear is expected to lose.
The problem for polar bears is they lack the ideal skull strength and tooth size needed for munching plants, grass, tree bark and berries, the scientists said.
Analyzing the biomechanics of their skulls reveals "polar bears would not be able to break up the food as well in their mouths and would not digest it as well," Van Valkenburgh said. Seal blubber is softer and requires less chewing, putting less strain on the skull by comparison.
Polar bears evolved from the brown bear relatively recently, and the two are closely related, with the split between them occurring 500,000 to 800,000 years ago in response to the rapid onset of glacial climates during the ice ages.
Polar bears are a "marvelous example of rapid adaptation to an extreme environment," Slater said. "The fact that we can lose them equally as rapidly as a result of human-mediated climate change is rather striking."
By Steve Gorman
http://uk.reuters.com/article/idUKTRE6AM6CV20101123
The research was based on 3-D computer modeling that compared the skull and jaw strength of the two bruins and found polar bears ill-suited to the tougher chewing demands posed by the largely vegetarian diet of their grizzly cousins.
The study, funded by the National Science Foundation, was conducted by evolutionary biologists at the University of California, Los Angeles, and published in an online journal of the Public Library of Science.
The findings add to mounting signs of threats to polar bears from global warming that scientists attribute to excessive levels of carbon dioxide and other heat-trapping "greenhouse gases" emitted by human activities, such as the burning of fossil fuels.
"This is one additional piece of evidence that things look pretty bleak for the polar bear, if current trends continue," said Graham Slater, the lead author of the research.
Polar bears already are losing habitat as rising Arctic temperatures diminish the sea ice they depend on to hunt for seals. As the ice continues to shrink, polar bears will be forced to seek additional food sources.
"To people who say polar bears can just change their diet, we are saying ... they will have to, but it probably will not be sufficient for them, especially if they are co-existing with grizzly bears," said Blair Van Valkenburgh, senior author of the paper.
Grizzlies, a subspecies of brown bears, have begun moving north in Canada as their natural habitat grows milder, while polar bears are being pushed farther south by melting ice, putting the two species together in territory best suited to the grizzly.
"These two species are already starting to come into contact," Slater said. And in the escalating competition for the plant life that makes up the bulk of the grizzly's diet, the polar bear is expected to lose.
The problem for polar bears is they lack the ideal skull strength and tooth size needed for munching plants, grass, tree bark and berries, the scientists said.
Analyzing the biomechanics of their skulls reveals "polar bears would not be able to break up the food as well in their mouths and would not digest it as well," Van Valkenburgh said. Seal blubber is softer and requires less chewing, putting less strain on the skull by comparison.
Polar bears evolved from the brown bear relatively recently, and the two are closely related, with the split between them occurring 500,000 to 800,000 years ago in response to the rapid onset of glacial climates during the ice ages.
Polar bears are a "marvelous example of rapid adaptation to an extreme environment," Slater said. "The fact that we can lose them equally as rapidly as a result of human-mediated climate change is rather striking."
By Steve Gorman
http://uk.reuters.com/article/idUKTRE6AM6CV20101123
Study sees polar bears losing out to grizzlies
(Reuters) - Polar bears are likely to lose out to grizzly bears in fierce competition for food as climate change drives the two species closer together into shared habitat, biologists concluded in a study released on Tuesday.
The research was based on 3-D computer modeling that compared the skull and jaw strength of the two bruins and found polar bears ill-suited to the tougher chewing demands posed by the largely vegetarian diet of their grizzly cousins.
The study, funded by the National Science Foundation, was conducted by evolutionary biologists at the University of California, Los Angeles, and published in an online journal of the Public Library of Science.
The findings add to mounting signs of threats to polar bears from global warming that scientists attribute to excessive levels of carbon dioxide and other heat-trapping "greenhouse gases" emitted by human activities, such as the burning of fossil fuels.
"This is one additional piece of evidence that things look pretty bleak for the polar bear, if current trends continue," said Graham Slater, the lead author of the research.
Polar bears already are losing habitat as rising Arctic temperatures diminish the sea ice they depend on to hunt for seals. As the ice continues to shrink, polar bears will be forced to seek additional food sources.
"To people who say polar bears can just change their diet, we are saying ... they will have to, but it probably will not be sufficient for them, especially if they are co-existing with grizzly bears," said Blair Van Valkenburgh, senior author of the paper.
Grizzlies, a subspecies of brown bears, have begun moving north in Canada as their natural habitat grows milder, while polar bears are being pushed farther south by melting ice, putting the two species together in territory best suited to the grizzly.
"These two species are already starting to come into contact," Slater said. And in the escalating competition for the plant life that makes up the bulk of the grizzly's diet, the polar bear is expected to lose.
The problem for polar bears is they lack the ideal skull strength and tooth size needed for munching plants, grass, tree bark and berries, the scientists said.
Analyzing the biomechanics of their skulls reveals "polar bears would not be able to break up the food as well in their mouths and would not digest it as well," Van Valkenburgh said. Seal blubber is softer and requires less chewing, putting less strain on the skull by comparison.
Polar bears evolved from the brown bear relatively recently, and the two are closely related, with the split between them occurring 500,000 to 800,000 years ago in response to the rapid onset of glacial climates during the ice ages.
Polar bears are a "marvelous example of rapid adaptation to an extreme environment," Slater said. "The fact that we can lose them equally as rapidly as a result of human-mediated climate change is rather striking."
By Steve Gorman
http://uk.reuters.com/article/idUKTRE6AM6CV20101123
The research was based on 3-D computer modeling that compared the skull and jaw strength of the two bruins and found polar bears ill-suited to the tougher chewing demands posed by the largely vegetarian diet of their grizzly cousins.
The study, funded by the National Science Foundation, was conducted by evolutionary biologists at the University of California, Los Angeles, and published in an online journal of the Public Library of Science.
The findings add to mounting signs of threats to polar bears from global warming that scientists attribute to excessive levels of carbon dioxide and other heat-trapping "greenhouse gases" emitted by human activities, such as the burning of fossil fuels.
"This is one additional piece of evidence that things look pretty bleak for the polar bear, if current trends continue," said Graham Slater, the lead author of the research.
Polar bears already are losing habitat as rising Arctic temperatures diminish the sea ice they depend on to hunt for seals. As the ice continues to shrink, polar bears will be forced to seek additional food sources.
"To people who say polar bears can just change their diet, we are saying ... they will have to, but it probably will not be sufficient for them, especially if they are co-existing with grizzly bears," said Blair Van Valkenburgh, senior author of the paper.
Grizzlies, a subspecies of brown bears, have begun moving north in Canada as their natural habitat grows milder, while polar bears are being pushed farther south by melting ice, putting the two species together in territory best suited to the grizzly.
"These two species are already starting to come into contact," Slater said. And in the escalating competition for the plant life that makes up the bulk of the grizzly's diet, the polar bear is expected to lose.
The problem for polar bears is they lack the ideal skull strength and tooth size needed for munching plants, grass, tree bark and berries, the scientists said.
Analyzing the biomechanics of their skulls reveals "polar bears would not be able to break up the food as well in their mouths and would not digest it as well," Van Valkenburgh said. Seal blubber is softer and requires less chewing, putting less strain on the skull by comparison.
Polar bears evolved from the brown bear relatively recently, and the two are closely related, with the split between them occurring 500,000 to 800,000 years ago in response to the rapid onset of glacial climates during the ice ages.
Polar bears are a "marvelous example of rapid adaptation to an extreme environment," Slater said. "The fact that we can lose them equally as rapidly as a result of human-mediated climate change is rather striking."
By Steve Gorman
http://uk.reuters.com/article/idUKTRE6AM6CV20101123
Friday, November 5, 2010
Polar bears can't eat geese into extinction
New statistical model demonstrates that trophic mismatch feeds bears without exterminating snow geese
As the Arctic warms, a new cache of resources—snow goose eggs—may help sustain the polar bear population for the foreseeable future. In a new study published in an early online edition of Oikos, researchers affiliated with the Museum show that even large numbers of hungry bears repeatedly raiding nests over many years would have a difficult time eliminating all of the geese because of a mismatch in the timing of bear arrival on shore and goose egg incubation.
"There have been statements in popular literature indicating that polar bears can extirpate snow geese quickly once they start to eat eggs," says Robert Rockwell, a research associate in the Division of Vertebrate Zoology at the Museum and a professor at the City University of New York. "However, there will always be the occasional mismatch in the overlap between the onshore arrival of bears and the incubation period of the geese. Even if the bears eat every egg during each year of complete 'match,' our model shows that periodic years of mismatch will provide windows of successful goose reproduction that will partially offset predation effects."
In the last few years, work along the Cape Churchill Peninsula of western Hudson Bay by Rockwell and colleagues has suggested that polar bears are not as hamstrung by their environment as many biologists believe. One new nutritional option for polar bears is the bounty of goose eggs which had previously hatched into goslings that were gone by the time bears came ashore. In recent years, 'early' bears have left breaking sea ice to come ashore and consume eggs. In fact, the earlier the bears come ashore, the better: eggs are higher in nutrients when the embryo is younger.
In the new Oikos paper, Rockwell and coauthors Linda Gormezano (also affiliated with the Museum) and David Koons (a researcher at Utah State University in Logan) simulated the timing of events during the Arctic spring: the break-up of sea ice, the movement of bears onto shore, the migration of geese to the North, and the laying of eggs. Results from the computer model show that the mismatch of timing is something that both the bears and geese can use to their advantage. The timing of geese migration is primarily based on photoperiod (the amount of light in 24 hours), which will not change as quickly as polar bear movements, which are based on the melting of sea ice.
Results show that the advance in mean overlap of the two species gives an advantage to polar bears. But increased variability, also the result of global climate change, leads to an increased mismatch that is good news for snow geese.
"Mismatch is often thought to be bad, but in this case periodic mismatch is good because it keeps geese from going extinct and allows polar bears to eat," says Rockwell. "Are polar bears adaptable? Of course. This could be a nice stable system. The geese aren't going to go away, and they are a nutrient resource for the bears."
http://www.eurekalert.org/pub_releases/2010-11/amon-pbc110410.php
As the Arctic warms, a new cache of resources—snow goose eggs—may help sustain the polar bear population for the foreseeable future. In a new study published in an early online edition of Oikos, researchers affiliated with the Museum show that even large numbers of hungry bears repeatedly raiding nests over many years would have a difficult time eliminating all of the geese because of a mismatch in the timing of bear arrival on shore and goose egg incubation.
"There have been statements in popular literature indicating that polar bears can extirpate snow geese quickly once they start to eat eggs," says Robert Rockwell, a research associate in the Division of Vertebrate Zoology at the Museum and a professor at the City University of New York. "However, there will always be the occasional mismatch in the overlap between the onshore arrival of bears and the incubation period of the geese. Even if the bears eat every egg during each year of complete 'match,' our model shows that periodic years of mismatch will provide windows of successful goose reproduction that will partially offset predation effects."
In the last few years, work along the Cape Churchill Peninsula of western Hudson Bay by Rockwell and colleagues has suggested that polar bears are not as hamstrung by their environment as many biologists believe. One new nutritional option for polar bears is the bounty of goose eggs which had previously hatched into goslings that were gone by the time bears came ashore. In recent years, 'early' bears have left breaking sea ice to come ashore and consume eggs. In fact, the earlier the bears come ashore, the better: eggs are higher in nutrients when the embryo is younger.
In the new Oikos paper, Rockwell and coauthors Linda Gormezano (also affiliated with the Museum) and David Koons (a researcher at Utah State University in Logan) simulated the timing of events during the Arctic spring: the break-up of sea ice, the movement of bears onto shore, the migration of geese to the North, and the laying of eggs. Results from the computer model show that the mismatch of timing is something that both the bears and geese can use to their advantage. The timing of geese migration is primarily based on photoperiod (the amount of light in 24 hours), which will not change as quickly as polar bear movements, which are based on the melting of sea ice.
Results show that the advance in mean overlap of the two species gives an advantage to polar bears. But increased variability, also the result of global climate change, leads to an increased mismatch that is good news for snow geese.
"Mismatch is often thought to be bad, but in this case periodic mismatch is good because it keeps geese from going extinct and allows polar bears to eat," says Rockwell. "Are polar bears adaptable? Of course. This could be a nice stable system. The geese aren't going to go away, and they are a nutrient resource for the bears."
http://www.eurekalert.org/pub_releases/2010-11/amon-pbc110410.php
Polar bears can't eat geese into extinction
New statistical model demonstrates that trophic mismatch feeds bears without exterminating snow geese
As the Arctic warms, a new cache of resources—snow goose eggs—may help sustain the polar bear population for the foreseeable future. In a new study published in an early online edition of Oikos, researchers affiliated with the Museum show that even large numbers of hungry bears repeatedly raiding nests over many years would have a difficult time eliminating all of the geese because of a mismatch in the timing of bear arrival on shore and goose egg incubation.
"There have been statements in popular literature indicating that polar bears can extirpate snow geese quickly once they start to eat eggs," says Robert Rockwell, a research associate in the Division of Vertebrate Zoology at the Museum and a professor at the City University of New York. "However, there will always be the occasional mismatch in the overlap between the onshore arrival of bears and the incubation period of the geese. Even if the bears eat every egg during each year of complete 'match,' our model shows that periodic years of mismatch will provide windows of successful goose reproduction that will partially offset predation effects."
In the last few years, work along the Cape Churchill Peninsula of western Hudson Bay by Rockwell and colleagues has suggested that polar bears are not as hamstrung by their environment as many biologists believe. One new nutritional option for polar bears is the bounty of goose eggs which had previously hatched into goslings that were gone by the time bears came ashore. In recent years, 'early' bears have left breaking sea ice to come ashore and consume eggs. In fact, the earlier the bears come ashore, the better: eggs are higher in nutrients when the embryo is younger.
In the new Oikos paper, Rockwell and coauthors Linda Gormezano (also affiliated with the Museum) and David Koons (a researcher at Utah State University in Logan) simulated the timing of events during the Arctic spring: the break-up of sea ice, the movement of bears onto shore, the migration of geese to the North, and the laying of eggs. Results from the computer model show that the mismatch of timing is something that both the bears and geese can use to their advantage. The timing of geese migration is primarily based on photoperiod (the amount of light in 24 hours), which will not change as quickly as polar bear movements, which are based on the melting of sea ice.
Results show that the advance in mean overlap of the two species gives an advantage to polar bears. But increased variability, also the result of global climate change, leads to an increased mismatch that is good news for snow geese.
"Mismatch is often thought to be bad, but in this case periodic mismatch is good because it keeps geese from going extinct and allows polar bears to eat," says Rockwell. "Are polar bears adaptable? Of course. This could be a nice stable system. The geese aren't going to go away, and they are a nutrient resource for the bears."
http://www.eurekalert.org/pub_releases/2010-11/amon-pbc110410.php
As the Arctic warms, a new cache of resources—snow goose eggs—may help sustain the polar bear population for the foreseeable future. In a new study published in an early online edition of Oikos, researchers affiliated with the Museum show that even large numbers of hungry bears repeatedly raiding nests over many years would have a difficult time eliminating all of the geese because of a mismatch in the timing of bear arrival on shore and goose egg incubation.
"There have been statements in popular literature indicating that polar bears can extirpate snow geese quickly once they start to eat eggs," says Robert Rockwell, a research associate in the Division of Vertebrate Zoology at the Museum and a professor at the City University of New York. "However, there will always be the occasional mismatch in the overlap between the onshore arrival of bears and the incubation period of the geese. Even if the bears eat every egg during each year of complete 'match,' our model shows that periodic years of mismatch will provide windows of successful goose reproduction that will partially offset predation effects."
In the last few years, work along the Cape Churchill Peninsula of western Hudson Bay by Rockwell and colleagues has suggested that polar bears are not as hamstrung by their environment as many biologists believe. One new nutritional option for polar bears is the bounty of goose eggs which had previously hatched into goslings that were gone by the time bears came ashore. In recent years, 'early' bears have left breaking sea ice to come ashore and consume eggs. In fact, the earlier the bears come ashore, the better: eggs are higher in nutrients when the embryo is younger.
In the new Oikos paper, Rockwell and coauthors Linda Gormezano (also affiliated with the Museum) and David Koons (a researcher at Utah State University in Logan) simulated the timing of events during the Arctic spring: the break-up of sea ice, the movement of bears onto shore, the migration of geese to the North, and the laying of eggs. Results from the computer model show that the mismatch of timing is something that both the bears and geese can use to their advantage. The timing of geese migration is primarily based on photoperiod (the amount of light in 24 hours), which will not change as quickly as polar bear movements, which are based on the melting of sea ice.
Results show that the advance in mean overlap of the two species gives an advantage to polar bears. But increased variability, also the result of global climate change, leads to an increased mismatch that is good news for snow geese.
"Mismatch is often thought to be bad, but in this case periodic mismatch is good because it keeps geese from going extinct and allows polar bears to eat," says Rockwell. "Are polar bears adaptable? Of course. This could be a nice stable system. The geese aren't going to go away, and they are a nutrient resource for the bears."
http://www.eurekalert.org/pub_releases/2010-11/amon-pbc110410.php
Wednesday, September 8, 2010
Polar Bear Sighted In Manitoba Far South Of Normal Range
Winnipeg Free Press · Tuesday, Aug. 31, 2010
Residents of a remote northern Manitoba First Nations community were startled on Sunday night to see a polar bear taking a dip in a river -- hundreds of kilometres south of the animal's usual range. The bear was a "good size" youngster, RCMP Sergeant Noel Allard said yesterday from Shamattawa, a First Nations community about 340 kilometres southeast of Churchill, where the bears are most famously spotted. RCMP kept a close eye on the bear until darkness fell, when it ambled off into the night. Sgt. Allard said that even local elders couldn't recall ever seeing a polar bear in the area, and that community residents were excited by the sighting. Manitoba Conservation officials will keep an eye out for the bear, RCMP said.
http://www.nationalpost.com/news/canada/toronto/Polar+Bear+Sighted+Manitoba+South+Normal+Range/3463827/story.html#ixzz0ywZ54lA4
Residents of a remote northern Manitoba First Nations community were startled on Sunday night to see a polar bear taking a dip in a river -- hundreds of kilometres south of the animal's usual range. The bear was a "good size" youngster, RCMP Sergeant Noel Allard said yesterday from Shamattawa, a First Nations community about 340 kilometres southeast of Churchill, where the bears are most famously spotted. RCMP kept a close eye on the bear until darkness fell, when it ambled off into the night. Sgt. Allard said that even local elders couldn't recall ever seeing a polar bear in the area, and that community residents were excited by the sighting. Manitoba Conservation officials will keep an eye out for the bear, RCMP said.
http://www.nationalpost.com/news/canada/toronto/Polar+Bear+Sighted+Manitoba+South+Normal+Range/3463827/story.html#ixzz0ywZ54lA4
Polar Bear Sighted In Manitoba Far South Of Normal Range
Winnipeg Free Press · Tuesday, Aug. 31, 2010
Residents of a remote northern Manitoba First Nations community were startled on Sunday night to see a polar bear taking a dip in a river -- hundreds of kilometres south of the animal's usual range. The bear was a "good size" youngster, RCMP Sergeant Noel Allard said yesterday from Shamattawa, a First Nations community about 340 kilometres southeast of Churchill, where the bears are most famously spotted. RCMP kept a close eye on the bear until darkness fell, when it ambled off into the night. Sgt. Allard said that even local elders couldn't recall ever seeing a polar bear in the area, and that community residents were excited by the sighting. Manitoba Conservation officials will keep an eye out for the bear, RCMP said.
http://www.nationalpost.com/news/canada/toronto/Polar+Bear+Sighted+Manitoba+South+Normal+Range/3463827/story.html#ixzz0ywZ54lA4
Residents of a remote northern Manitoba First Nations community were startled on Sunday night to see a polar bear taking a dip in a river -- hundreds of kilometres south of the animal's usual range. The bear was a "good size" youngster, RCMP Sergeant Noel Allard said yesterday from Shamattawa, a First Nations community about 340 kilometres southeast of Churchill, where the bears are most famously spotted. RCMP kept a close eye on the bear until darkness fell, when it ambled off into the night. Sgt. Allard said that even local elders couldn't recall ever seeing a polar bear in the area, and that community residents were excited by the sighting. Manitoba Conservation officials will keep an eye out for the bear, RCMP said.
http://www.nationalpost.com/news/canada/toronto/Polar+Bear+Sighted+Manitoba+South+Normal+Range/3463827/story.html#ixzz0ywZ54lA4
Wednesday, August 25, 2010
Polar bear threat to Solway geese
Polar bears have been eating thousands of eggs after becoming stranded23 August 2010
An Arctic expedition has confirmed fears that polar bears are preying on the eggs of barnacle geese who migrate to the Solway Firth each winter.
During a recent trip, scientists discovered evidence of bears eating thousands of eggs.
The bears have turned to the eggs after being stranded on land in the summer months as a result of diminishing ice.
The Wildfowl and Wetlands Trust (WWT) is concerned bird numbers could be devastated if the situation continues.
Zoologist Brian Morrell, of the WWT Wetlands centre at Caerlaverock on the north Solway coast, recorded the increased polar bear activity while monitoring a barnacle goose colony on the Arctic island of Svalbard as part of an expedition organised by Jouke Prop and a team from Branta Research from Groningen in the Netherlands.
He said 10 polar bears were seen roaming the colony, with one bear eating more than 1,000 eggs at one sitting.
Of more than 500 nests on the island, fewer than 40 were successful and most of them had very small clutch sizes of only one or two goslings.
Mr Morrell said: "The geese are very long-lived birds and ironically their survival rate is increased if they don't actually breed, especially the females.
"But if their breeding continues to be affected in this way the population will quickly age, which threatens its stability and the future conservation of this bird which is very special to WWT."
The entire population of Svalbard barnacle geese winter on the Solway Firth and return to breed in the Arctic each summer.
Last winter only half the expected numbers of goslings were seen as the flocks returned to the Solway and it is thought the situation may be similar this winter.
Ironically, Svalbard barnacle goose numbers have increased from 300 to more than 30,000 thanks to conservation efforts over the past 60 years.
As increasing numbers of polar bears forage on the islands, researchers hope the geese will adapt in time to reduce the damage to the total population.
Mr Morrell added: "Some of the goose colonies in Svalbard use cliffs to nest. Although that has its own problems for fledgling chicks, it does put the nests out of reach of marauding bears.
"It seems this will eventually be the only breeding strategy left to the geese."
http://www.blogger.com/post-create.g?blogID=4348728589329576621
(Submitted by Mo Holkar)
Tuesday, May 25, 2010
Polar bears face 'tipping point' due to climate change
Tuesday, 25 May 2010By Matt Walker
Editor, Earth News
Climate change will trigger a dramatic and sudden decline in the number of polar bears, a new study has concluded.
The research is the first to directly model how changing climate will affect polar bear reproduction and survival.
Based on what is known of polar bear physiology, behaviour and ecology, it predicts pregnancy rates will fall and fewer bears will survive fasting during longer ice-free seasons.
These changes will happen suddenly as bears pass a 'tipping point'.
Details of the research are published in the journal Biological Conservation.
Educated guesses
Until now, most studies measuring polar bear survival have relied on a method called "mark and recapture".
This involves repeatedly catching polar bears in a population over several years, which is cost and time-intensive.
Because of that, the information scientists have gathered on polar bear populations varies greatly: for example, datasets span up to four decades in the best studied populations in Western Hudson Bay and Southern Beaufort Sea, but are almost non-existent for bears in some parts of Russia.
Even more difficult is measuring how survival and reproduction might change under future climatic conditions.
"Some populations are expected to go extinct with climate warming, while others are expected to persist, albeit at a reduced population size," says Dr Peter Molnar of the University of Alberta, Edmonton, Canada.
However, these projections are essentially educated guesses, based on experts judging or extrapolating how current population trends might continue as the climate changes.
"So we've looked at the underlying mechanisms of polar bear ecology to assist our understanding of what will happen in a warming world," Dr Molnar told the BBC.
Fasting and mating
Dr Molnar, Professor Andrew Derocher and colleagues from the University of Alberta and York University, Toronto focused on the physiology, behaviour and ecology of polar bears, and how these might change as temperatures increase.
"We developed a model for the mating ecology of polar bears. The model estimates how many females in a population will be able to find a mate during the mating season, and thus get impregnated."
Male polar bears find females by wandering the ice, sniffing bear tracks they come across. If the tracks have been made by a female in mating condition, the male follows the tracks to her.
The researchers modelled how this behaviour would change as warming temperatures fragment sea ice.
They also modelled the impact on the bears' survival.
Southern populations of polar bears fast in summer, forced ashore as the sea ice melts.
As these ice-free seasons lengthen, fewer bears are expected to have enough fat and protein stores to survive the fast.
By developing a physiological model that estimates how fast a bear uses up its fat and protein stores, the researchers could estimate how long it takes a bear to die of starvation.
"In both cases, the expected changes in reproduction and survival were non-linear," explains Dr Molnar.
"That is, as the climate warms, we may not see any substantial effect on polar bear reproduction and survival for a while, up until some threshold is passed, at which point reproduction and survival will decline dramatically and very rapidly."
The US Endangered Species Act lists the polar bear as "Threatened".
The latest US assessment of the conservation status of polar bears included the only two previous studies to assess the impact of climate change, but these extrapolated population trends, rather than directly modelling how the ecology of polar bears may alter.
The new study by Dr Molnar's team offers a way to improve these predictions, and suggests the potential for even faster declines than those found by the US assessment.
"Canada has about two-thirds of the world's polar bears, but their conservation assessment of polar bears didn't take climate change seriously," says Dr Molnar, a flaw noted by the IUCN/SSC Polar Bear Specialist Group last year.
"Our view is that the Canadian assessment should be redone, properly accounting for climate change effects.
"The status of polar bears is likely much more dire than suggested by the Canadian report," he adds.
"For instance, for a while we will only see small changes in summer fasting season survival in Western Hudson Bay.
"[But] eventually mortality will dramatically increase when a certain threshold is passed; for example, while starvation mortality is currently negligible, up to one-half of the male population would starve if the fasting season in Western Hudson Bay was extended from currently four to about six months."
http://news.bbc.co.uk/earth/hi/earth_news/newsid_8700000/8700472.stm
(Submitted by Liz R)
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