Polar bears have always had problems finding enough to eat. They can only efficiently Hunt out on the sea ice which in the past many seasons of plenty and seasons of fast. Climate change has made the seasons of fast too long to be survived by many and so they’ve had to adapt.
At the same time humans have been increasingly invading the polar bears territory and taking land for both all exploration and other activities.
It appears that this is pushing some polar bears to such extreme lengths that they have started to cannibalize one another. Given the precarious situation that the polar regions have have polar bears cannot afford another pressure on there population. We must reduce the disturbance to stop this unnatural behaviour from becoming common.