The diet of the blue-footed booby consists solely of fish. When gliding over the surface the water, the blue-footed booby keeps its beak at a downward angle, watching for fish. The species is known for its spectacular dives from heights of up to 80 feet. Barely making a splash when hitting the water, the blue-footed booby resurfaces several yards away with a fish. Unique among other boobies, the blue footed booby can dive below the water from a surface swimming position to catch fish. Despite its habit of feeding alone, the blue-footed booby cooperate in flocks to hunt fish. When one bird in the flock spots a fish, it gives a whistle to alert the others. Then the rest of the flock follows the first diving, into the water with perfectly synchronized movements. Interestingly, the male and the female are adapted for catching prey of different sizes. The male, being smaller, performs shallow dives, while the heavier female is able to make deeper dives farther offshore.