TEHRAN, Young Journalists Club (YJC) - Scientists say polar bears, the Arctic apex predators, need larger quantities of energy to survive than previously thought, warning that changing sea ice conditions, as a consequence of climate change, is making their prey increasingly inaccessible.
According to a new study, whose alarming results were published in the journal Science on Friday, polar bears, due to their demanding lifestyle, are more vulnerable to undernourishment than once thought.
The research reveals that the bears have greater daily energy demands, 1.6 times higher than what previous studies showed, and more than any other apex carnivores.
To conduct their study, Anthony Pagano, a research biologist at the US Geological Survey (USGS), and his colleagues attached high-tech tracking collars to nine female polar bears they had captured on the sea ice of the Beaufort Sea in a bid to measure their efforts to find food on the thawing Arctic ice for 8 to 12 days during the springs of 2014, 2015, and 2016.
Along with tracking the polar bears’ hunting and survival activities during this critical season, the researchers measured the metabolic rates of each bear using blood and urine samples. In order to have a bear's-eye view, they also strapped GPS-camera collars to the animals to record and film their activity.
“We found that polar bears actually have much higher energy demands than predicted. They need to be catching a lot of seals,” Pagano said.
As global warming steadily thaws the amount of sea ice in the Arctic, bears will miss opportunities to catch their favorite prey—fatty, calorie-rich ringed seals—and many will weaken and starve, burning muscle mass.