Blacktip Reef Shark

What to look for

Identify them by their fins. The black tips on the dorsal and caudal fins are very obvious. These sharks usually measure 1.6 m in length. They stay in shallow water.

Look for a sleek body. You will see them cruising near the reef edge because they hunt small fish. While they look fast, they often move with a steady rhythm. I first spotted one clearly in 2014 near Koh Tao.

Behaviour you’ll observe

They are active hunters. These sharks spend much time in the upper 15 m of the water column. They rarely dive deep.

Watch their movement patterns. You might see a group of three or four cruising together near a coral head. Since they are quite shy, they often dart away if your fin touches the sand. I saw a group of five sharks at Richelieu Rock during a night dive in 2018. They stayed close to the reef slope.

Where and when

You can see them often. Sighting probability is high, roughly 1 in 3 dives in many Thai reef locations. They prefer shallow, sunlit areas.

Specific sites offer better chances. At Richelieu Rock, they frequent the sandy patches between coral outcrops. You should visit between February and May for the best visibility. Another good spot is Koh Tao where they inhabit shallow reef flats.

In Komodo, they live near the shallower bays. I found them frequently at sites like Manta Point if you stay in the shallowest sections. They prefer warm water.

Diver etiquette

Keep your distance. You should maintain at least 3 m of space between you and the shark. Do not chase them.

Stay calm and still. If you move too fast, the shark will likely swim away because it perceives you as a threat. Never touch the animal.

Watch your buoyancy. Avoid kicking up sand near their heads. This keeps the water clear and prevents the shark from feeling crowded.

Conservation status

The IUCN Red List classifies them as Vulnerable. This status changed after recent population surveys showed significant declines. Many sharks are caught as bycatch.

Local fishing pressure is high. In some parts of Southeast Asia, reef sharks face heavy pressure from artisanal fisheries. We must support marine protected areas to help them recover. Protecting their habitat is the only way forward.

Summary of facts

Feature	Data
Avg Length	1.6 m
Max Depth	30 m
IUCN Status	Vulnerable
Sighting Rate	~33%

Check your fins before you enter the water. If you are a nervous diver, practice your buoyancy in a calm pool before heading to high-current reef sites.