The Eye-opening Science Of Close Encounters With Polar Bears

For the last four decades experts from the Norwegian Polar Institute (NPI) have been keeping tabs on the health and movement of polar bears (Credit: AFP)

It's a pretty risky business trying to take a blood sample from a polar bear -- one of the most dangerous predators on the planet -- on an Arctic ice floe.

First you have to find it and then shoot it with a sedative dart from a helicopter before a vet dares approach on foot to put a GPS collar around its neck.