"There are a few easy-to-spot signs of an angry polar bear. A growl may be an attempt to warn you about something, and usually is the sound of a defensive bear. Hissing and snorting is what you want to look out for, because these are signs of aggression. As well, if its head is lowered and its ears are laid back, prepare for an attack. One common misconception is that if a bear goes on its hind legs, it means it is extremely aggressive. Really though it's just being curious and is trying to find a way to get a better look at you."