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Bonnethead shark

Sphyrna tiburo

Description: The Bonnethead shark (Sphyrna tiburo) is one of the smaller species of hammerhead sharks. Its shovel-like snout is broadly rounded. They are gray-brown above and lighter on the underside. Bonnetheads are the only known sharks to exhibit sexual dimorphism (the heads of adult males and females are different in shape).

Size: Bonnetheads reach an average size of 36- 48 inches (91-122 cm),with a maximum length of approximately 59 inches (150 cm), with females reaching greater lengths than males. The maximum recorded weight of a Bonnethead is 24pounds (10.8 kg).

Behavior: The Bonnethead is an active tropical shark that swims in small groups of up to 15 individuals, but sometimes migrating schools of hundreds have been reported. It is a timid and a harmless shark (only one attack on humans has ever been recorded).

Diet: They feed primarily on crustaceans, consisting mostly of blue crabs, but also shrimp, mollusks and small fishes.

Senses: Like other sharks, it is capable of electroreception (ability to perceive natural electrical stimuli) to detect its prey. Their field of vision is increased due to the fact that their eyes are located on the far sides of their head.

Communication: It uses a special body fluid, called “cerebrospinal fluid” or “Cl-excess” to let others know it is in the area.

Reproduction: The Bonnethead is viviparous, reaching sexual maturity at about 30 inches (76 cm). They typically reproduce every year. The mother is pregnant for 4.5 to 5 months, which is the shortest known shark gestation period.

Habitat/range: This species is abundant within inshore, coastal, continental and insular shelf areas within its range and commonly found in estuaries, shallow bays and channels, mud and sand flats and reef habitats. They are found in the Western Atlantic (Rhode Island and North Carolina to the Caribbean and southern Brazil) and in the Eastern Pacific (southern California to Ecuador).

Status: Listed as Least Concern on IUCN Red List.