“She might have been desperate,” Pagano speculated. This bear even leapt into the sea in a failed attempt to catch a seal swimming by. One bear lost close to 44 pounds, including her lean muscle, in 10 days. Measurements showed those animals lost 10 percent or more of their body mass. The videos revealed that four of the females weren’t able to catch a single seal. That’s about 60 percent more than previous studies had estimated. The data showed the bears were active about 35 percent of the time and resting for the remainder, yet they burned through 12,325 calories a day, much of it from their body reserves.

Blood and urine samples were taken again and the video and other data were downloaded. One bear had moved 155 miles away by that time. Eight to 11 days later they were all re-captured. The bears were fitted with GPS collars that had cameras to record point-of-view videos of each. Pagano’s study involved capturing nine female bears in the Beaufort Sea off Alaska last April, when there are normally lots of seals around. Or they stay on land longer, spending the summer and, increasingly, the fall fasting, living off their fat from the seals they caught in the spring. In the late spring, the ice is breaking up sooner and forming later in the fall, forcing bears to burn huge amounts of energy walking or swimming long distances to get to any remaining ice. Even today, in the middle of the bitter cold Arctic winter, satellites show there is about 770,000 square miles less sea ice than the 1981 to 2010 median (That's an area larger than Alaska and California combined). Photograph by Tom Murphy, National Geographic Disappearing Ice Makes for Hungrier BearsĬlimate change is heating up the Arctic faster than anywhere else, and sea ice is shrinking 14 percent per decade. The bay is famous for polar bears, but their population is in decline. That’s why the melting of the Arctic sea ice threatens polar bear survival.Ī polar bear watches her cubs on the Hudson Bay in Manitoba, Canada. “They’re far more successful doing this than any other method of hunting,” Pagano said. Then the bear bites it on the neck and drags it onto the ice. When a seal surfaces to breathe the bear stands on its hind legs and smacks it on the head with both of its front paws to stun it.

To minimize their energy consumption the bears still-hunt, waiting for hours by seals’ cone-shaped breathing holes in the sea ice. Polar bears rely almost exclusively on a calorie-loaded diet of seals. “Our study reveals polar bears’ utter dependence on seals,” said lead author Anthony Pagano, a wildlife biologist with the U.S. Turns out they are high-energy beasts, burning through 12,325 calories a day-despite sitting around most of the time, according to a unique metabolic analysis of wild bears published Thursday in Science. Without examining the bear in the video-thought to have died-it’s impossible to know for sure what ailed that individual, but now scientists have published new findings that shed more light on the risk to the species overall.īecause of melting sea ice, it is likely that more polar bears will soon starve, warns a new study that discovered the large carnivores need to eat 60 percent more than anyone had realized.

Shot by Paul Nicklen and Cristina Mittermeier of the nonprofit group Sea Legacy, and published on National Geographic in early December, the video ignited a firestorm of debate about what scientists know, and don’t know, about the impacts of global warming on polar bears. Millions have seen the heart-wrenching video of a polar bear clinging to life, its white hair limply covering its thin, bony frame.

Iceberg picture polor bear