Otters are known as being playful. However, having watched a bunch of them at Woodland Park Zoo, I have to think that they are on some serious drugs. The speed with which they flew around the enclosure, wrestled with each other, lay in the water getting blasted by the water jets and generally acted like hooligans, you would think this was a vast waste of precious energy for a creature in the wild. I think they must metabolize something in their food to create something like cocaine or speed. What other reason could there be?