The term 'fish eater' can be summarized by two crossword solutions: OSPREY (6 letters) and Ern (3 letters). An OSPREY is a large bird of prey that is found on every continent except Antarctica. It is also known as a fish hawk because it primarily feeds on fish. Ern is a type of stork found in Africa, Asia, and Europe. It is a large wading bird that feeds mainly on fish, frogs, and other aquatic animals.