The occurrence of yellowfin tuna at Espiritu Santo Seamount in the Gulf of California

Pelagic fishes are not evenly dispersed in the oceans, but aggregate at distinct locations in this vast and open environment. Nomadic species such as mackerels, tunas, and sharks form assemblages at seamounts . Fishermen have recognized this behavior and have placed moorings with surface buoys in deep waters to provide artificial landmarks, around which fish concentrate and are more easily captured. These fish aggregating devices (termed FADs) are common in the tropical oceans .In a sense, it may only be the larger size that separates a seamount from a man-made FAD.