Mostly inshore and around beaches; also in channels and other deeper areas. Doesn't mind murky water. From about 30-900 ft; females cruise in shallower areas – average 223 ft. Found inshore and offshore, on continental and insular shelves and adjacent deep water. Common at bays, river mouths and in harbors; avoids sandy beaches and the surf zone, coral reefs and rough bottom, and surface waters. Coastal-pelagic, but usually bottom associated at 1-280 m. Sometimes in oceanic waters. Known to make extended seasonal migrations in some parts of its range. Feeds mainly on bony fishes, also small sharks, cephalopods, and shrimps, rays and gastropods. Youngs feed heavily on crustaceans such as blue crabd and mantis shrimp. Viviparous. Sexual dimorphism is evident in thickness of skin layer of maturing and adult females. Females live as long as 21 year; males 15 years. Populations are segregated by age. Young readily kept in aquaria. Utilized for human consumption, for leather and oil. Marketed fresh, smoked, dried-salted and frozen; fins are valued for soup. Used in Chinese medicine. Records to 300 cm TL uncertain. TL to 300 cm. Angling: an inshore fish and a good light-tackle fighter