Blacktip reef shark

What it is

This requiem shark has a streamlined body with a short, rounded snout and large oval eyes. Its most striking feature is the black tips on all fins, particularly the first dorsal and tail fins. The upper body is greyish-brown while the underside is white, separated by a pale band. Adults typically reach 1.6 metres in length, though some grow to two metres. Females are generally larger than males. The teeth are triangular with serrated edges, designed for gripping slippery prey.

Where it lives

It inhabits nearshore waters across the tropical Indo-Pacific region. In the Indian Ocean, it ranges from South Africa and Madagascar to India and Southeast Asia. In the Pacific, it is found from China and the Philippines to Australia and Hawaii. It prefers shallow depths of a few metres over reef ledges and sandy flats. While primarily marine, it enters brackish estuaries and occasionally freshwater lakes in Malaysia and Madagascar.

How it lives

Active and fast-swimming, this shark hunts small teleost fish, squid, crabs, and sometimes sea snakes. It often patrols reef edges and may herd mullet against the shore. Individuals show strong site fidelity, staying in small home ranges for years. They are timid towards humans but may bite legs in shallow water if provoked by food. Larger sharks like tigers and groupers prey on juveniles. They lack colour vision but detect movement and electrical fields from prey.

Breeding and life cycle

Females give birth to live young, usually two to five pups per litter. Reproductive cycles vary by location, occurring annually in some regions and biennially in others. Gestation lasts between seven and sixteen months. Mating involves males tracking chemical signals from females and biting their fins. Newborns stay in very shallow, protected waters where they form large groups during high tides to avoid predators.

Fish and people

Fishermen harvest this shark for its meat, fins, and liver oil, though it is not a major commercial target. Its timid nature makes it popular for diving tourism, but accidental bites can occur when wading. The species holds no specific cultural role mentioned in records, but its presence is a key indicator of reef health. Local communities in the Indo-Pacific may encounter it frequently in coastal waters.

Status and threats

The International Union for Conservation of Nature lists this species as Vulnerable. Despite being widespread, local populations have declined due to overfishing and habitat degradation. Its slow reproduction rate makes recovery difficult. Fishing pressure on reefs and pollution threaten its numbers. Conservation efforts focus on managing fisheries and protecting coral reef ecosystems where it resides.

Questions people ask about Blacktip reef shark

Good reading and sources

• Blacktip reef shark on WikipediaEncyclopedia
• More photos on Wikimedia CommonsPhotos
• Wikidata recordOpen data