The Pacific viperfish, Chauliodus macouni, is a predatory fish that lives in the abyssal depths of the deep sea. In daytime it can be found from 200–5000 m below the ocean surface. At night it swims up into shallower depths of less than 200m where food is more plentiful. Pacific viperfish will mostly eat crustaceans and small fish. They typically reach lengths of up to 1 foot and are considered an example of deep-sea gigantism.