Hammerhead shark is a shark with an unusually wide, flattened head. The head is shaped like a hammer or a shovel. One eye and one nostril are located at each end of the head. There are 10 species of hammerhead sharks. Different species have slightly different head shapes.
Hammerhead sharks live in tropical and warm temperate seas worldwide. They are found in coastal waters and in the open ocean. Some species live alone, but others may form schools of hundreds of individuals. Hammerhead sharks range in size from the bonnethead, which is about 5 feet (1.5 meters) long, to the great hammerhead, which may reach about 20 feet (6.1 meters).
The shark’s wide head provides extra space for sensing organs that help the shark find food. The position of the nostrils may help the shark track a scent when searching for food. The widely spaced eyes may aid in scanning surroundings. The head shape also helps the shark maneuver quickly while swimming.
Hammerheads eat a variety of fish and shellfish. They rarely bite people. Five hammerhead species are critically endangered—that is, they are likely to become extinct in the near future. Hammerheads are threatened by overfishing.
