Alewife is a species of ocean herring with a bluish-grey to olive back with silvery sides. The body is wide, narrows at the belly, and averages 6” in length. They have large eyes, a prominent black spot near the gill cover, and a forked fin.
The round goby is a small, soft-bodied fish with a distinctive black spot on the first dorsal fin. They have large, protruding eyes and range in length from 4″ to 10″. While juveniles are grey, adult round gobies have grey, black, brown, and olive green markings.