I often answer questions while feeding the fish and marine life when diving at Shedd Aquarium.  One of the most frequently asked questions is, “aren’t you afraid to be diving with those hammerhead sharks?”  I generally answer the question in 2 parts.  First these are not hammerhead sharks, they are Bonnethead sharks, and no I am not afraid, we humans are not on their food chain.

The bonnethead, Sphyrna tiburo, also called shovelhead, is a smaller version of the hammerhead shark. Its odd-shaped head contains a multitude of electroreceptors to detect minute electromagnetic disturbances.

Like its hammerhead cousin, the bonnethead feeds by swimming across the sea floor, moving its head in an arc pattern like a metal detector.

Bonnetheads feed primarily on crustaceans, consisting mostly of blue crabs, but also eat shrimp, mollusks and small fishes. To expand its food choices, the shark has small, sharp teeth in front for grabbing soft prey, and flat, broad molars in back for crushing hard-shelled animals.

When its electroreceptors detect a meal hidden in the sand, the shark turns sharply and bites into the sediment. If it’s a crab, the shark uses its teeth to grind the shell, then uses suction to swallow the crab whole.

On average, bonnetheads are about 3 and a-half feet long. They range from New England, where they are rare, to the Gulf of Mexico and Brazil, and from southern California to Ecuador. In spring, summer and fall, they are found off Florida and in the Gulf of Mexico.

Bonnetheads are not considered dangerous to humans. They usually swim in small groups of five to 15 individuals, though schools of hundreds or even thousands have been reported.