Sphyrnidae

Smooth hammerhead

Sphyrna zygaena

A smooth arc leading hundreds of young

• Gray
• White
• Tropical
• Nearshore
• Globally widespread
• Marine fish
• Fusiform
• Large
• Tropical fish

Characterized by an unnotched, smoothly curved cephalofoil, the smooth hammerhead is a large, powerful pelagic shark capable of tolerating significantly cooler oceanic temperatures than its tropical congeners. The anterior margin of its broad hammer-like head forms a continuous, graceful arc that completely lacks a central indentation, giving the species its common name. The dorsal coloration ranges from deep olive-grey to dark brownish-grey, contrasting with a clean white belly, and the sickle-shaped first dorsal fin is moderately tall with a rounded tip. Circumglobally distributed through temperate and subtropical oceans worldwide, it patrols coastal bays, continental shelves, and pelagic offshore waters down to two hundred meters depth. Energetic schools undertake extensive seasonal migrations toward higher latitudes in summer. As an apex predator, it pursues schooling teleosts including mackerels and herrings, while utilizing the wide sensory head to track squid, skates, and stingrays along coastal floors. Viviparous with large litters numbering between twenty and fifty pups, maximum recorded total length reaches five hundred centimetres.

Sources: NOAA Fisheries — Smooth Hammerhead Shark, Sphyrna zygaena