Scalloped Hammerhead Shark

Sphyrna lewini

Maximum Size:

14 ft (4.3 m), 990 lb (449 kg)


About 35 years.

Typical depth:

3–984 ft (1–300 m)


Scalloped hammerhead sharks are found worldwide in tropical and warm temperate marine waters. Their hammer-shaped snout, known as a “cephalofoil” is scalloped with deep grooves, hence their name. Scalloped hammerheads specialize in hunting stingrays buried in the sand, but they also feed on grouper, snapper, crustaceans and other shark species. They are most often seen on offshore reefs, drop offs and seamounts where they sometimes form large schools. Scalloped hammerheads pair up to reproduce, and pregnancy can last up to 12 months. Depending on her size, female sharks can give birth to as many as 30 shark pups, usually during mid-summer.


Larger shark species, such as tiger sharks, and orcas (killer whales).


Although attacks on humans by scalloped hammerhead sharks are rare, they have been known to cause injury if they feel threatened or cornered. Warning signs of an attack include head swings, exaggerated swimming, back arching and lowered pectoral fins. Attacks usually result in biting or raking with the teeth, which can cause deep lacerations. The severity of shark bites often depends on the species that bites. Attacks on humans by scalloped hammerhead sharks do occur, but there are no known fatalities.


Exit the water as soon as possible. Rinse the affected area with soap and water. Apply pressure to control the bleeding and elevate the affected limb above the heart. It is not unusual for someone bitten by a shark to require treatment for shock. In this case, keep them warm, calm and in the shade, and do not provide anything to eat or drink. Lay the person on their back and elevate their legs above their head. Seek medical attention as soon as possible, even for minor bites, which will probably require cleaning and suturing.


The treatment advice contained in this book is meant for informational purposes only and is not intended to be a substitute for professional medical advice, either in terms of diagnosis or treatment. Always seek the advice of your physician or other qualified health provider if you are injured by a marine organism. Never disregard professional medical advice or delay seeking it because of something you have read in this book.