Often seen feeding at the surface; reported caught between 8,500 to 15,000 ft; in Hawaii, rarely found north of Kauai. World's largest fish, which is harmless to humans. Specimens rarely above 12 m. Often seen offshore but coming close inshore, sometimes entering lagoons or coral atolls. Sometimes seen cruising near outer wall. Reported to frequent shallow water areas near estuaries and river mouths, sometimes during seasonal shrimp blooms. Found singly, or in aggregations of over 100 individuals. Often associated with groups of pelagic fishes, especially scombrids. Highly migratory between ocean basins and national jurisdictions, but returns to the same sites annually. Feed on planktonic and nektonic prey, such as small fishes (sardines, anchovies, mackerel, juvenile tunas and albacore), small crustaceans and squids. Often seen in a vertical position with the head at or near the surface when feeding. When actively feeding on zooplankton the sharks turn their heads from side to side, with part of the head lifted out of the water, and the mouth opened and closed 7-28 times per minute; these suction gulps were synchronized with the opening and closing of the gill slits. Ovoviviparous, litter size is over 300 pups. Females of 438 to 562 cm are immature (FIGIS 09/2003). Utilized fresh, frozen, dried and salted for human consumption, liver processed for oil, fins used for shark-fin soup, offal probably for fishmeal, cartilage for health supplements and skin for leather products. Used in Chinese medicine. Highly valued commodity in ecotourism operations. Populations have been depleted in several countries by harpoon fisheries