Spotted moray eel

Photo: Kevin Bryant · CC BY-NC-SA

Spotted morays are ambush predators that occupy crevices and caves during the day, emerging at night to hunt fish and crustaceans. Their continuous open-mouth posture is a respiratory behavior, not aggression — they must pump water over their gills by opening and closing their jaws. Morays play an important role in controlling populations of small reef fish and are known to cooperate with hunting groupers: groupers signal to morays with a head-shake gesture, and the moray flushes prey from crevices the grouper cannot enter.