Coney Island whitefish
"Coney Island whitefish" is the slang name for a used condom seen floating in New York waters or seen on the beach. Jon Lighter's Historical Dictionary of American Slang has a citation from 1980, but the speaker there is quoted that he'd heard the term used in Brooklyn in 1969 or 1970.
"Coney Island whitefish" shows up in Google Groups on August 4, 1989. "East River eel" (a seldom-used variant) shows up in Google Groups on September 20, 2000.
25 April 1984, New York Times, pg. C20:
At 37 years of age, he (comedy director Rob Reiner - ed.) is, he says, the oldest member of his local softball team, the Coney Island Whitefish, league champions in two of the last three seasons.
"Coney Island whitefish" shows up in Google Groups on August 4, 1989. "East River eel" (a seldom-used variant) shows up in Google Groups on September 20, 2000.
25 April 1984, New York Times, pg. C20:
At 37 years of age, he (comedy director Rob Reiner - ed.) is, he says, the oldest member of his local softball team, the Coney Island Whitefish, league champions in two of the last three seasons.