Smooth Hammerhead

Smooth hammerhead (Sphyrna zygaena) - stock photos, illustrations & facts

Conservation status | Threatened > Vulnerable
Scientific classification | Kingdom: Animalia > Phylum: Chordata > Class: Chondrichthyes > Order: Carcharhiniformes > Family: Sphyrnidae > Genus: Sphyrna > Species: S. zygaena
Binomial name | Sphyrna zygaena

The smooth hammerhead, Sphyrna zygaena, also known as the common hammerhead, is a large hammerhead shark...
more »

Smooth hammerhead (Sphyrna zygaena) - stock photos, illustrations & facts

Conservation status | Threatened > Vulnerable
Scientific classification | Kingdom: Animalia > Phylum: Chordata > Class: Chondrichthyes > Order: Carcharhiniformes > Family: Sphyrnidae > Genus: Sphyrna > Species: S. zygaena
Binomial name | Sphyrna zygaena

The smooth hammerhead, Sphyrna zygaena, also known as the common hammerhead, is a large hammerhead shark that mainly inhabits temperate coastal waters throughout the world. It is highly valued for its fins, which are used in shark fin soup, primarily in East Asian countries. This species is considered potentially dangerous to humans, yet only 2 fatalities can be attributed to all 9 species in the Sphyrna genus.

Smooth hammerheads are found along coasts in temperate oceans, but are also found along some tropical coastlines as well, namely on the west coast of Africa and in Southeast Asia. They are also found in the Mediterranean Sea. This species lives on continental shelves, though they are sometimes spotted in deeper waters. They are often seen swimming at the surface with their dorsal fin poking out of the water. They are found alone or in small groups, and sometimes form large schools of over 100 when migrating to cooler waters in summer.

The smooth hammerhead can reach a maximum length of 5 m (16 ft), though the average is smaller, about 3 m (10 ft). Maximum weight is 400 kg (882 lbs). They may live for 20 years or longer. They are typically brown in color, but may range from dark grayish-brown to olive brown to gray, but always with a lighter underbody. Pectoral fins may have black tips. Its hammer-shaped head, called a cephalophoil, is broad and flat, with a large eye at the end of each lobe. It gets its name "smooth" hammerhead because its cephalophoil is not clearly notched, like that of the scalloped hammerhead. In particular, it has no central notch at the end of its snout, making it fairly easy to identify.

Smooth hammerheads feed on bony fish, small sharks, skates and rays. They also feed on schooling fish, such as herring or mackerel. Smooth hammerheads are viviparous, giving birth in summer to litters of from 20-40 live pups. Pups are about 50 cm (20 in) at birth. Pups and juveniles fall prey to large sharks, but adult hammerheads are thought to have few enemies except for killer whales and man.

Smooth hammerheads are taken by longlines and caught as bycatch in driftnets throughout the world. Their meat is sometimes sold for human consumption, but is not considered particularly desirable in the West. Their liver oil is used for vitamins, as it's rich in vitamin A. The skin is sometimes used for leather products, such as boots. Their fins are highly rated for shark fin soup, and all remaining parts are used in Chinese medicine and fishmeal. This species is presumed to be taken in large numbers, and is currently rated as Vulnerable by the IUCN Red List.
« less