Despite being the largest land carnivore and a top Arctic predator that can weigh over 600 kg, polar bears start off surprisingly small. Blind, almost hairless, and weighing just 600g at birth, cubs are born in maternity dens under the snow. These snow caves keep newborns warm and safe for the first few months of their life, when they grow rapidly by nursing on their mother’s rich milk.
After three to four months in the den, cubs will have grown to about 20 times their birth weight and will be large enough and furry enough to follow their mothers out into the frigid Arctic spring.
In a study published in The Journal of Wildlife Management, we used remote cameras to study polar bear families as they emerged from their dens in Svalbard, Norway, gaining insight into the behaviour of mothers and cubs as they experience the world outside the den for the first time.