Common to mainland America, the midshipman fish (Porichthys notatus) has golden
spots on each side like the brass burrons on a midshipman's coat. Familiar along
the Pacific coast, the luminescent midshipman is also called "the talking fish,"
the "grunter," the "grunt" and the 'singing fish." The sound it makes when
disturbed - made by vibrating the air bladder - is actually similar to the croak
of a tree frog. Other "talking fish" include the triggerfish, which is called
Humuhumunkunukn-a-puaa, "fish that grunts like a pig," by Hawaiians, and the
male codfish, which grunts, both to defend its spawning area and to urge females
to lay eggs. A Gulf of Mexico toadfish species has an air bladder that actually
produces "a powerful hooting sound . . . resembling a boat whistle," according
to one.