Young parrotfishes (Scaridae family) are small and drab. As they mature, they change colors, often becoming a purplish red. Finally, the females can change sex, and become what is called a terminal male, a large and beautiful blue or green. This sleeping terminal male has, like many parrotfish species, created a cocoon of mucous for themselves at night, and is sleeping or under a coral ledge; scientists think that the mucous may make it harder for predators to find the parrotfish.

This parrotfish was photographed at night in about 35 feet of water off the south Kohala Coast near the Mauna Lani Resort on the Big Island of Hawaii.