Blacktail Reef Shark

About the Blacktail Reef Shark

Blacktail Reef Sharks, also called Grey Reef Sharks, can be spotted in many places around the world as their range is widespread. They occur in the central Pacific Ocean and west onwards to the eastern Indian Ocean usually between depths of 10 to 50 m near coral reefs. However, they can dive to 1000 m deep.

Biology and Behaviour

Blacktail reef sharks are dark grey to bronzy-grey with an off-white underside. They have a stout body, a broad, round snout and large eyes. Their upper and lower jaw each have 13 to 14 teeth. They have a long black margin along the entire posterior edge of their caudal fin. Their dorsal fin may have a white edge, their second dorsal, anal, pectoral and pelvic fins have dusky or black tips.

Although they are active during the day, they are even more active at night. They are fast swimmers and form schools near their favourite areas. They feed mainly on bony fish, but sometimes will prey on squids, octopuses and crustaceans. 

Like many other animals, grey reef sharks will become aggressive when harassed. When they are harassed, they will perform a threat display that involves a hunched posture — a sign that they are ready to attack.

Reproduction and Lifespan

Blacktail reef sharks are viviparous. Female blacktail reefs reproduce every other year with a 12-month gestation periods with small litter sizes between one to six pups. The size at birth for pups is between 50 to 75 cm.

Males mature between 120 to 140 cm long and can grow up to 185 cm. Females mature around 125 cm and can attain a length of 190 cm in about seven years. The maximum length reported was a male at 255 cm long. The lifespan for grey reefs is at least 25 years.

Conservation and Tourism

The IUCN lists blacktail reef sharks as near threatened. However, some of the most important reef diving sites in the Maldives have led to sharks to be under protection as they have become a lucrative tourist attraction business for diving.

Do you have images or videos of Blacktail Reef Sharks?
Submit them to [email protected].