Bonnethead
Sphyrna tiburo
Smooth hammerhead
Sphyrna zygaena
About
The smooth hammerhead is a large, wide-ranging shark that copes with cooler water better than any other hammerhead. It grows up to 5 m long and 400 kg, though most adults are closer to 3.35 m.
- Length
- 3.4 m · max 5 m
- Weight
- max 400 kg
- Depth
- 0–20 m
How to tell it apart
Several hammerhead species share this stretched-out head shape. Look at the front edge of the hammer: on the smooth hammerhead it curves smoothly across, with no central notch, unlike the scalloped hammerhead's indented front margin.
Appearance
The head is flattened and spread sideways into a wide, short hammer shape, with an eye at each end. The body is streamlined, with a tall, curved first dorsal fin. The back is dark brownish grey to olive, lighter on the flanks, with a white belly.
Habitat
Found worldwide, reaching further into cool temperate waters than any other hammerhead, from the surface down to about 200 m and usually within the top 20 m. It ranges widely across the Atlantic, Indian, and Pacific Oceans, including the Mediterranean Sea.
Behaviour
Adults are usually solitary or in small groups, but young sharks can form large schools of hundreds during their seasonal migrations. In hot weather they sometimes swim near the surface with the dorsal fin breaking the water. It hunts fish, rays, other sharks, and squid, and will readily scavenge food caught on fishing lines.
Did you know?
Stingrays are a favourite prey, and one shark examined by researchers was found with 95 stingray spines lodged in and around its mouth.
Log it in Into the Blue
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