The bonnethead shark is a small species of hammerhead shark living in the warm waters of the Americas. It is one of the smallest and most studied hammerhead sharks.

The bonnethead shark is easily recognized by its shovel-shaped or rounded hammer-like head, which is much more compact than that of other hammerhead sharks. It typically measures about 32 inches in length, with a maximum size of around 5 feet.

Its body is gray-brown on the upper side and lighter on the underside. Its more rounded head allows it to move efficiently in shallow waters and better detect its prey.

The bonnethead shark is mainly found in the warm waters of the western Atlantic, from North Carolina on the east coast of the United States down to Brazil in South America, as well as in the Gulf of Mexico and the Caribbean, and also in parts of the eastern Pacific from California to Ecuador.

The bonnethead shark mainly inhabits shallow coastal areas such as bays, estuaries and seagrass beds, where it often stays near the bottom but can also be found at depths of up to about 260 feet.

The bonnethead shark is often observed in small groups.

The bonnethead shark feeds mainly on crabs, shrimp, mollusks and small fish, and has the rare ability among sharks to digest seagrass, making it partially omnivorous.

The bonnethead shark is viviparous, with a gestation period of 4 to 5 months, giving birth to 4 to 14 well-developed pups measuring about 14 to 16 inches in length.

The bonnethead shark is listed as many other marine species within The IUCN Red List of threatened species. The bonnethead shark appears in the IUCN Red List since 2021 within the category Endangered !