GREAT HAMMERHEAD (Sphyrna mokarran)

Recognition: The great hammerhead is characterized by a nearly straight anterior margin of the head (slightly rounded in very young specimens) with a deep central indentation, and by pelvic fins with curved rear margins The teeth are triangular with strongly serrated edges, with cusps that become increasingly oblique towards the corners of the mouth.

Color: Color varies from olive green to brownish gray above, shading to white below.

Size: This is the largest of the hammerheads and it is reputed to reach 610 cm (20 ft).

Similar species: All the other hammerheads lack the strongly serrated teeth and the pelvic fins with curved rear margins.

Biology: This large shark is circumtropical and can be found in both the open ocean and in shallow coastal waters. It ranges from North Carolina to Florida and the Gulf of Mexico. Most great hammerheads seen off the U.S. east coast are very large specimens (larger than 240 cm). Juveniles are seldom seen in our area.

Economic importance: The flesh, like that of other hammerheads, is not utilized in the U.S.A. because dealer and consumer bias against its darker flesh. Its very large fins are among the most valuable.

Fishing: It is caught both in inshore and offshore longline operations.

Carcass: Hammerhead carcasses are not usually landed because there is little demand for their flesh. Great hammerheads are usually finned and the carcasses are discarded. Carcasses of this species can be usually differentiated from other hammerheads by their much larger size. The caudal peduncle of great hammerheads is about 180 mm (6 in) from top to bottom, a size seldom reached by the other species. It is also more rectangular than those of the scalloped and smooth hammerheads. References