For nearly a decade, researchers have gathered camera footage from outside the dens of female polar bears and their cubs on Svalbard, shedding light on the behaviors linked to denning.

Polar bear mothers in the Arctic generally give birth in early January around the start of the new year. The cubs are born completely blind, do not have their signature snow-colored fur, and generally weigh about one pound.

At birth, polar bears are blind, nearly hairless and weigh just over a pound—about the same as a loaf of bread. But they spend their first few months snuggled inside a snowy den, fattening up on their mother’s milk.