As the Arctic continues to warm, scientists are learning about the changing climate and the impact of the growing polar bear population.
It has been a particularly warm winter, with the mercury reaching 40 degrees Fahrenheit (7 degrees Celsius) at the end of April, according to the U.S. National Oceanic and Atmospheric Administration.
While some scientists have attributed this winter to the melting of ice, some have questioned the notion that warmer temperatures are causing more polar bears to die.
“The bears are just not there yet,” said Peter DeWitt, an Arctic researcher at the University of Maryland.
“And I think we’re going to see more deaths.”
The polar bear in Alaska.
A new study published in the journal Polar Biology suggests that the polar bears’ winter death rate has been rising steadily since the end-2013 climate change.
The study also found that the death rate is increasing more rapidly in the southern polar region, where there is more snow.
“We found a very strong correlation between the temperature change in the Arctic and the number of polar bears that die,” said DeWit.
The research indicates that warmer winters and the increase in polar bear mortality are a direct result of the increased amount of CO2 in the atmosphere.
The polar bears in the northern Arctic have a similar winter death pattern to the ones in the south, where the animals are generally more active, according the study.
Researchers found that in the summer of 2013, when the winter death of the Arctic bears was the highest it had ever been, the number killed was the second highest on record, behind the 2011 deaths of 2,400 bears.
But by March 2016, when temperatures were already beginning to warm again, the total number of Arctic bears killed was still at its lowest level, the study found.
In the summer, the polar fur seals were in a similar situation, with a total death rate of about 1,100 deaths.
But by April 2016, the population was down to about 604, and that number had remained stable over the summer.
The study also noted that in addition to the deaths in the polar regions, there were fewer polar bears left in the wild.
DeWitt said that polar bears are typically solitary animals that prefer to stay in their territory, and this is what has led to the decrease in the population.
“The bears have a tendency to go away,” he said.
“They want to find a better place to live.”