United States scientists captured and fitted collars equipped with Global Positioning System and "bear cam" to nine cub-less female bears. Less sea ice means the bears have to work harder to find them.
"You're talking a pretty incredible amount of mass to lose", said US Geological Survey wildlife biologist Anthony Pagano, lead author of the study.
The scientists also analysed blood and urine samples taken at the beginning and end of each bear's 8-11 day journey across the ice fields to ascertain the animal's metabolic rate.
The problem is that many polar bears can't seem to find enough food to satisfy their high energy requirements.
Although polar bears have a larger range than other bears, the study also showed that because of declining sea ice the bears are having to swim and walk further than before to find seals, which increases energy expenditure.
"In the Beaufort Sea we are seeing that the ice is retreating much further to the north than it had historically", Mr Pagano said. The bears, therefore, are ending up burning more energy during the summer as they are fasting until the ice returns in the fall. But later in the year, after the bears' long summer fast, those young seals are older and wiser, meaning polar bears are not able to catch as many. Metabolic tracers were used to determine how much energy the bears expended. For example, scientists have thought that since the bears are primarily "sit-and-wait" hunters, they would minimize their energy use while hunting.
Their energy consumption as calculated during the study was 1.6 times higher than previously thought.
The scientists estimated that an active female polar bear needed around 51 megajoules of energy a day. "This study identifies the mechanisms that are driving those declines by looking at the actual energy needs of polar bears and how often they're able to catch seals".
Polar bears are listed as threatened under the US Endangered Species Act and as vulnerable by the International Union for the Conservation of Nature - a designation just short of endangered on both lists.
As the sea ice cover on Earth's polar regions continues to fragment and diminish, it has a clear and negative impact on some regional populations of polar bears in the Arctic.
"As they reduce that amount of time it follows that they catch fewer seals total and they are taking in a lower amount of energy". Then they attacked them by jumping on them. Previous studies found other animals are going without food longer than they did in the 1980s and 1990s, the study notes.
Paris readies for floods as Seine surges larger
Unusually heavy rains have engulfed scenic quays, wine cellars and museum basements in Paris as Seine River appears rain-swollen. Nearly 1,500 people have been evacuated after the swollen River Seine rose further, raising fears of severe flooding in Paris .
So what happens when times are tough?
All over the Arctic, scientists have seen evidence of weakened polar bears, Pagano said.
As the ice dwindles, "we are essentially pulling the rug out from underneath the polar bears", Durner said. "Polar bears are reliant on seals for food and seals rely on sea ice".
But more tracking and monitoring will be necessary to fully understand what's happening to the bears.
Canada, home to two-thirds of the world's population of roughly 30,000 polar bears, has done a good job surveying subpopulations, making sure the polar bear trade is legally regulated, and incorporating traditional knowledge into polar bear management, the WWF said.
"You might get a very different picture on weight gain from many more individuals", he said.
Knicks and Joakim Noah looking to part ways
GM Scott Perry said earlier in the season he did not want to do that , as he liked having Noah's veteran presence around. As the Daily News reported, Noah shouted at Hornacek after being removed from last week's loss to the Warriors.
Almost 100 people were killed over the prolonged election period, mostly in clashes between Odinga supporters and police. Odinga took his oath to the deafening cheers of supporters before speaking briefly and swiftly departing.
The Las Vegas Review-Journal reports that more than 300 documents related to the shooting were unsealed by court order on Tuesday. Court officials are redacting the warrant records in preparation for release later Tuesday.
"To try to make this right, Epic is offering a full refund to every Paragon player for every purchase on any platform", it says. Did any of you guys play Paragon? The refund will come directly from Epic Games instead of platform providers or retailers.
Treasury Secretary Steven Mnuchin says the report released by his office will lead to new sanctions against Russian Federation . The remaining 96 names are those of businesspeople, all with a net worth of more than $1 billion, according to BBC.
David Ige reportedly struggled to remember his Twitter password so he could tell everyone that the alert was just an error. Now we're told confusion arose when conflicting messages were sent in a test of the system during a shift change .
Damascus has denied using any chemical weapons in the seven-year conflict, blaming the rebels on using it on themselves. Several children were also affected, the group said. "We will pursue accountability", she said, writing on Twitter.
And make no mistake, there is no doubt that Fisher will be in shape at some point before the February 26 deadline. The veteran player intends to begin skating and training on his own before joining the gold team for practices.
DeRozan produced his 36th game with at least 20 points despite shooting 6 of 18 from the floor and missing 5 of 6 3-point tries. This was the most points scored in a game this season and the most scored by a player in franchise history for the Rockets.
Spoofing involves placing bids to buy or offers to sell futures contracts with the intent to cancel them before execution. The CFTC said Deutsche Bank had agreed to pay $30m to civil charges in the case, covering a period from 2008 to 2014.
But fiesty Kim wasn't about to let that kind of shade slide, and quickly fired back: 'You know what's confusing... She was undoubtedly referring to LiLo's sudden change in accent, which fans first noticed a little while back.
Nintendo Change overtakes the Wii U
The Wii U was released in 2012, and from that time to when production ended a year ago , Nintendo sold just 13.56 million units. When the Switch was released in spring 2017, there were questions about if Nintendo would be able to survive as a console maker.
Wall to miss 6 weeks due to knee injury
With the scores tied at 96, Thunder forward Josh Huestis tried to find Adams in the paint but the pass was intercepted. Oklahoma City will now have a day off, before meeting the Denver Nuggets in Denver on Friday.
Syrian opposition: Turkey to represent us at Sochi summit
The Congress wrapped up with a final statement that set up a 150-member committee tasked with creating a draft constitution. Representatives from various countries and global organizations were also invited as observers of the congress.
Three lunar phenomena to occur on one night at a time
If you would rather watch it from the comfort of your home, NASA will be streaming a live broadcast while it occurs. Rather, it comes from the fact this will be the second full moon we see in the month of January, which is rare.
1 magnitude quake rattles northern Afghanistan: USGS
However, no casualties or damage have been reported yet in India but one person died and several injured in Balochistan. There have been no reports of damage in Kabul or in Islamabad, both of which were shaken by the impact.