shark
Scalloped hammerhead.
Sphyrna lewini · also: Hammerhead
Instantly recognisable for its scalloped, wing-shaped head, this shark forms some of the ocean's most spectacular schools — sometimes hundreds strong — around seamounts. The wide "hammer" spreads electroreceptors for detecting buried prey and gives near-360° vision. In the Maldives it is a deep, dawn-channel prize for experienced divers.
Size
~3.5–4.3 m
Weight
Commonly ~80–100 kg; max ~150 kg.
Diet
Bony fishes and cephalopods, plus crustaceans, smaller sharks and rays.
Lifespan
~20–30 years (max ~35).
Depth
Surface to ~1,000+ m; schools gather in cooler, deeper water by day.
Reproduction
Live-bearing; large litters of ~15–31 pups after ~12-month gestation.
Snorkel or dive
Dive only — advanced (deep, dawn)
Best season
Rasdhoo peak Dec–Mar; Fuvahmulah more year-round
Conservation
Critically Endangered
How to recognise it
Wide flattened hammer head with a scalloped/notched front margin.
Behaviour
Often schools in deeper water by day; rises toward dawn; shy of divers' bubbles.
Where to see it in the Maldives
Rasdhoo Atoll (pre-dawn Hammerhead Point) and Fuvahmulah in the deep south.
Conservation
Critically Endangered — devastated by the fin trade; juveniles hit hard in coastal nurseries.
IUCN · Critically Endangered
Watch them responsibly
Stay calm and minimise bubbles (they're shy of scuba exhaust); keep distance and don't split a school.
The wide head spreads its electroreceptors over a larger area to detect buried prey.
The hammer is a hydrofoil that aids tight turns and a sensory array that sweeps the seabed like a metal detector.
Collective noun: a shiver of sharks
Want to dive with scalloped hammerhead?
Our Maldives specialists match you to the right atoll, season and resort.
Sightings are typical, not guaranteed — encounters vary with season and conditions.