Marine life  /  Sharks & rays  /  Grey reef shark
Reviewed 2026-09-06
Species entry

Grey reef shark

Carcharhinus amblyrhynchos

A broad black rear edge to the tail, and a threat display divers should know how to read.

Size
To 190 cm
Depth
5–40 m
Habitat
Reef edges and channels, Coral Sea
Active
Day and night
Range
Indo-Pacific
Rarity
Australia
2 stars of 5, usually seen in a week
SP-01
grey reef shark · full body · habitat
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To about 190 cm, grey above and white below, with a broad black margin along the rear edge of the tail, dusky tips to the other fins and no white dorsal tip. The tail marking is the reliable separation from the whitetip and blacktip reef sharks.

It patrols drop-offs and channels where current runs, usually in loose groups by day, and hunts reef fish and cephalopods. It is one of the few sharks with a well-described threat display: an arched back, lowered pectoral fins, a raised snout and an exaggerated rolling swimming pattern, performed when the animal feels cornered — against a wall, in a cave mouth, or by a diver approaching directly. The correct response is to stop closing and back away along the reef rather than swim at it. Numbers across the Coral Triangle are much reduced and the species is listed as endangered. Recorded from about 5 to 50 m.

Where to find:

LocationRarity Best monthsDepthHabitat
Australia Australia editorial estimate
2 stars of 5, usually seen in a week
Year-round
5–40 m
Reef edges and channels, Coral Sea
Papua New Guinea Papua New Guinea editorial estimate
3 stars of 5, a good week should turn one up
Year-round
5–50 m
Drop-offs, channels and current-swept reef
Bali Indonesia editorial estimate
4 stars of 5, two or three a season
Year-round
5–50 m
Walls and drop-offs
Anilao Philippines editorial estimate
5 stars of 5, a handful of records
Year-round
5–45 m
Reef slopes and drop-offs

Ratings are per location: 1 means found on most dives that look for it, 5 means a handful of records. Where enough dives have been logged the figure is calculated from them; otherwise it is an editorial estimate, and says so. We publish habitat and destination, not the dive site.

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