Queer Fish Meaning

Example : 1919, W. Somerset Maugham, The Moon and Sixpence, chapter 54:  To these people, native and European, he was a queer fish, but they were used to queer fish, and they took him for granted; the world was full of odd persons, who did odd things; and perhaps they knew that a man is not what he wants to be, but what he must be.1974 April 21, Vincent Canby, "Movie Review: The Conversation," New York Times (retrieved 24 Feb 2014):  Harry is a queer fish indeed. He is suspicious of everybody and everything.