Aren’t polar bears the only animal that actively hunts humans?
Not quite. The polar bear doesn't know that we are a food source so won't normally bother with the tiny, textile clad creatures it sees far away the on horizon from time to time. But if they come up close and take a bite just to test if we're any good, they will immediately learn that they have found a great source of protein that is much easier to hunt than seals. So from then on they will actively hunt for humans and in Svalbard that means they will find the habitated areas within not too long. This is why the official policy is that a polar bear that has had their first taste of human flesh must be killed immediately.
While on the topic, this tourist is a cunt for not setting up proper security around his tent. The bear that bit him had to die to protect the resident human population.