So in other words, the researchers wanted a grant to study cortisol levels in polar bear hair, and in order to increase their chances of getting funding, they decided to tie their study to a climate change issue.
If you read the article, all it says is that they have been able to prove that cortisol in hair can be correlated with stress.
There appears to be nothing in the study that actually relates to climate change per se.
It seems to be pure spin that all polar bear stress could be related to climate change.
I’m guessing the polar bears are hibernating now which should be fairly relaxing.