Details
Sphyrna lewini
The scalloped hammerhead is a wide-ranging ocean shark of the Atlantic, Indian, and Pacific oceans. Its expanded head aids prey detection, and it may form loose schools.
Map: Ecoregions 2017 © RESOLVE (CC BY 4.0) · Natural Earth (PD)
It uses tropical and warm-temperate offshore waters, island slopes, and coastal seas. Young often gather in shallower nursery areas before ranging more widely.
Length is about 150-430 cm and weight about 30-150 kg. The laterally expanded hammer-shaped head, slim body, and tall dorsal fin are distinctive.
It swims across day and night and may gather around seamounts or islands. The broad head spreads sensory organs, helping it search broad patches of seafloor.
It is carnivorous, eating fish, squid, crustaceans, and rays. Its head shape and sensory systems help locate prey near the bottom.
It is live-bearing, with young developing inside the mother before birth. Juveniles grow in coastal or shallow nursery grounds that offer some refuge.
Its status is listed as Critically Endangered. Fishing for fins and meat, along with bycatch, makes careful international management important.
