Arctic ice from 1979 to the present has shrunk by an average of 13% each year. The polar bear and the narwhal are among the species most threatened by the melting of the Arctic ice. Journal of Experimental Biology study, also published by The Guardian, explained this problem.
Experts said: "From time immemorial these large mammals, predators like the polar bear and the narwhal or not, have adapted their nature, their DNA to the Arctic icy environment. Now these rapid changes are a desperate struggle for them."
"The consequences of climate warming on the enormous increase in energy use needed by these predatory mammals will be a significant drop in their living numbers before we know it." The melting of the Arctic ice threatens their hunting techniques for feeding, forcing these animals to a slow agony and projecting them towards an end that has been threatened for years, but which few are doing to avert.
According to the study, the polar bear lives in the cold by consuming as little physical energy as possible, hunting seals that with their fat provide them with sufficient calories, waiting to meet them, or digging holes in the ice to lure them to the surface and trapped.
Now it is often necessary to swim for three or four days to reach its prey: this means that the bear has to spend three to four times more energy to get food. The narwhal must dive and resurface quickly to hunt down the Greenland cod and return to the surface to breathe.
He can dive fast up to 1500 meters, but his body's oxygen supply is limited. The mobile ice sheets increasingly block his emergence, often making him risk death by drowning. The study also said that as in a chain reaction, climate change threatens not only polar bears and narwhals, but other Arctic species, from the Beluga whale, to the Arctic fox, to the musk ox.