Reef Shark

The Grey Reef Shark is one of the most abundant and widely recognized reef-associated sharks across the Indo-Pacific, belonging to the requiem shark family Carcharhinidae. It is a key mid-to-upper level predator on coral reef edges and drop-offs, often seen patrolling in loose groups by day. Adults typically reach 1.5-1.9 meters. The species is important to reef ecosystem balance and has become central to shark ecotourism at numerous dive destinations. It is currently assessed as Endangered due to its slow reproductive rate and vulnerability to fishing pressure across much of its range.

• Stout, streamlined gray body with a broad, rounded snout and darker gray back fading to a pale belly
• Large, round eyes and a relatively short mouth
• Distinctive solid black trailing margin on the tail fin, unlike the white-tipped fins of related reef species
• Plain or lightly edged first dorsal fin, without prominent white markings
• Broad-based, rounded pectoral fins and a stocky, muscular build compared to other requiem sharks The solid black rear edge of the caudal fin, without white tips elsewhere on the body, is the most reliable feature separating it from blacktip and whitetip reef sharks.

Grey Reef Sharks are found throughout the tropical Indo-Pacific, from the Red Sea and East Africa across to French Polynesia and Hawaii, typically along coral reef flats, drop-offs, and lagoon slopes. They favor clear water near reef edges at depths from the surface down to about 60 meters, showing strong site fidelity to particular reef systems. Juveniles often use shallow reef flats and lagoons as nursery habitat, while adults range more widely across outer reef slopes and channels, sometimes gathering in numbers near strong currents where prey concentrates.

Grey Reef Sharks are active, often forming loose daytime aggregations near reef drop-offs and becoming more solitary, active hunters at night. They feed primarily on reef fishes and cephalopods, using bursts of speed to chase prey among coral structures. Notably, this species can display a distinctive threat display, arching its back and lowering its pectoral fins, when it feels cornered or threatened. Reproduction is viviparous, with females producing small litters of about 1-6 pups annually or biennially after a roughly year-long gestation. As a key reef predator, it helps regulate populations of mesopredatory fish.