Sunday, September 16, 2018

"Over the past half dozen years, Researchers have studied interactions at bowhead whale carcass sites in Alaska"............"They found Grizzly Bears came out on top in 124 out of 137 confrontations with Polar Bears".............. "This, despite grizzilies being almost half the size of polar bears(Grizzlies clock in at 400–790 lbs (180–360 kg) for males .versus Polar Bear males weighing in at 772–1,543lbs (350–700 kg)".............Scientists had previously speculated that beached dead whales could be a partial dietary alternative for Polar Bears as they confront less year round sea ice to hunt seals, their preferred food..............Warming temperatures have encouraged Grizzlies to expand their habitat northward,, allowing them to become intraspecific-species competiitors with their Polar Bear cousins...............Those same warming conditions have led Dophins to swim up to the Arctic in Spring rather than during their historical Summer sojourn, with the ever problem-solving Polar Bears beginning to hunt them in their quest to "live long, prosper and avoid eventual extinction................Changing environmental conditions throwing multiple "monkey-wrenches" into the life cycles of the Bears of the north

View video of Polar Bears feasting on dead whale on Wrangel Island in Siberia
https://www.youtube.com/watch?v=tXitmDMxz3U

https://www.dailymail.co.uk/sciencetech/article-3352642/Battle-ice-bears-Arctic-grizzlies-taking-hungry-polar-bears-feeding-whale-carcasses-Alaska-winning.html


Sarah Griffiths; 12/9/15


Battle of the ice bears! Arctic grizzlies are taking on hungry polar bears feeding on whale carcasses in Alaska... and winning

  • Researchers studies interactions at bowhead whale carcasses in Alaska

  • They found grizzlies came out on top in 124 out of 137 confrontations

  • This is the despite the grizzilies being almost half the size of polar bears

Retreating sea ice is forcing some polar bear populations to increasingly forage for food on land during summer and autumn.
While washed-up bowhead whale carcasses make a good meal for the hungry bears, they are also proving a battleground between two species.
Biologists have witnessed polar bears fleeing the rich source of nutrients after being chased away by smaller Arctic grizzly bears, which can be almost half the size of their polar cousins.
There are concerns the aggressive behaviour could put polar bear populations under even more stress at a time when there are concerns about global warming harming their habitat













Each autumn, both species are attracted to Kaktovik in Alaska, to dine on whale carcasses, which are discarded by local hunts from communities living along the Alaskan portion of the Beaufort Sea coast.
'Relatively large numbers of polar bears and some grizzly bears use these resources, creating a competitive environment among species and social classes,' the study says.
'Relatively large numbers of polar bears and some grizzly bears use these resources, creating a competitive environment among species and social classes,' the study says. A family of foraging grizzlies are shown left and a family of polar bears in Alaska, right - both are stock image












Biologists from the US Fish and Wildlife Service, Marine Mammals Management in Alaska recorded the interactions between the apex predators between 2005 and 2007.
They found the smaller grizzly bears regularly come out on top. 
While polar bears are often seen as solitary hunters, as many as 20 have been recorded harmoniously sharing a carcass.
But when the grizzlies arrive, the scene can get ugly.
The aggressive bears are sometimes twice as small as the large polar bears, but this doesn't stop them chasing the larger predators away
Sometimes, they did not return for another snack.
The researchers said: 'Interspecific interactions [those between different species] were less frequently aggressive than intraspecific interactions [those between bears of the same species], but polar bears were more likely to be displaced from the feeding site by grizzly bears than by conspecifics [a member of the same species'.
The experts also observed different bears at the feeding site at different times of day. For example, polar bear families tended to dine at dawn and dusk, while lone adult polar bears and Arctic grizzly bears chose to feed at night.
They study says female bears with cubs were the most likely to act aggressively to other polar bears as well as grizzlies.
The team hopes their study, published in the Journal of Mammalogy, will shed light on the plight of bears forced further onto land.

POLAR BEARS SEEN EATING DOLPHINS FOR FIRST TIME 

In July, Norweigian scinetists documented pola bears eating dolphins in the Arctic.
They believe global warming may be behind the strange behaviour.
Usually, dolphins only go up north during the summer, but warmer warmers have caused them to arrive in spring, only for some to be devoured by hungry polar bears.
Polar bears feed mainly on seals so Jon Aars at the Norwegian Polar Institute was shocked to see dolphins being eaten by a bear.









In July, 2015, Norwegian scientists
 saw polar bears eating dolphins in 
the Arctic (pictured) – and they say 
global warming is to blame. 'It is
 likely that new spe
cies are appearing in the diet of 
polar bears due to climate change
 because new species are finding 
their way north,' said Jon Aars at 
the Norwegian Polar I
nstitute
'It is likely that new species are appearing in the diet of polar bears due to climate change because new species are finding their way north,' he said.
The first incident he documented was in April 2014 when his team came across a polar feeding on the carcasses of two white-beaked dolphins.
Although dolphins are regularly seen in the Norwegian Arctic in the summer months when the ice has melted, they have never been observed during winter or spring when the sea is usually still covered in sheets of ice.
But Norwegian scientists have reported a strong retreat of ice and two nearly ice-free winters in recent years which they said could have attracted the dolphins further north.
They say they probably became trapped by the sudden arrival of dense ice blown into a fjord by strong northerly winds.
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https://www.google.com/url?rct=j&sa=t&url=https://thebarentsobserver.com/en/arctic/2018/09/dead-whale-arctic-beach-can-be-feast-more-polar-bears&ct=ga&cd=CAEYACoUMTQ2NzQ5MTYyMzcyMTkzNTI0MTkyGmI1MDMzODcyZmNlOWY1OTk6Y29tOmVuOlVT&usg=AFQjCNGkSmHhoQaVShBrZTB3HHaaGZrCcg

Dead whale on Arctic beach can be feast for more than polar bears

The whale that this week stranded on the shores near Longyearbyen, Svalbard, should have been used as attraction for tourists, says local researcher Bjørn Frantzen.
September 11, 2018


Looking for the bear on Svalbard. Photo: Atle Staalesen
Polar Bears feasting on dead whale; Photo: The Governor of Svalbard
The “Polarsyssel” tow the dead whale from the shore of the Isfjorden. Photo: the Governor of Svalbard

The polar bears with great delight ate from the dead whale that drifted ashore in Isfjorden, near Longyearbyen. But the joy of the bear mother and her two cubs did not last long.

On Monday, the local Svalbard Governor decided to remove the dead animal and the cadaver was towed out at sea. The bears were driven away by the guards from the governor’s office. The site is located only few kilometers away from Longyearbyen, the local town with a population of about 2,000
Photos taken by the Governor’s Office and published by local newspaper Svalbardposten show the vessel «Polarsyssel» towing the animal to sea.
Not everyone is happy with the decision. Instead of towing the dead whale to sea and let it sink, it should have been towed to a safe place where the polar bears could continue their feast, says Bjørn Frantzen.
The researcher and senior adviser for the Norwegian Institute of Bioeconomy Research (NIBIO) argues that the dead whales regularly drifting ashore on the Arctic archipelago can serve as great tourist attractions.
«The authorities should together with the local population and tourist companies positively look for places that are suitable for stranding of dead whales,» he says to the Barents Observer.
Let the dead whale become a resource for local tourism,» he underlines.
Currently, local authorities in Svalbard always tow dead whales out at sea. But time is ripe for a change in that practice, Frantzen argues. «After all, we Norwegians love to go to exotic places to experience big predators, and when it happens abroad we think that it is quite ok.»
According to the researcher, the dead whales should be towed to a beach where they do not pose a threat to people. Then, tourist boats could come to site to view the polar bears.
A dead whale can provide food for polar bear for many months. When a dead bowhead whale stranded on the Russian Arctic island of Wrangel in fall 2017, it attracted more than 200 polar bears.  There was food enough for everyone and tourists got the sight of their life as their cruise vessel passed the site. The attraction would be predictable and can be planned in advance, it would be a win-win situation for everyone,» Franzen says. Furthermore, it would give a major fuel-saving effect for the tourist boats, he maintains.
Tourism is growing quickly in the Norwegian archipelago and visitors are all eager to get a glimpse of the powerful Arctic animal







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