The gray reef shark (Carcharhinus amblyrhynchos) is one of the most iconic sharks found on coral reefs throughout the Indo-Pacific.

The gray reef shark has a streamlined, powerful body perfectly adapted for fast swimming. Adults generally measure between 5 and 6.6 feet in length, although the largest individuals can exceptionally reach up to 8.4 feet.

Its back is gray to bronze-gray, while its belly is white, a coloration that allows it to blend into its surroundings when observed from above or below. Its main identification feature is the broad black edge along the rear margin of its caudal fin. The tips of the other fins also show more subtle black markings, particularly on the second dorsal fin.

Its snout is relatively rounded, and its large eyes provide excellent vision, essential for locating prey in the clear waters of coral reefs. Its mouth is equipped with several rows of triangular, serrated teeth, perfectly suited for grasping and tearing fish.

The gray reef shark is found in tropical waters of the Indian and Pacific oceans, from the eastern coast of Africa, the Red sea, and the Maldives to Australia, Papua New Guinea, the Philippines, Indonesia, southern Japan, and numerous Pacific islands, including French Polynesia, the Marshall islands, and Hawaii.

This species is absent from the Atlantic ocean.

The gray reef shark mainly inhabits outer coral reefs, steep reef slopes, and channels where currents bring a large amount of food. It is most often found from a few feet deep to around 200 feet, although it can occasionally descend much deeper.

During the day, several individuals may form small groups that slowly patrol above the reef or remain facing into the current to conserve energy. At night, they generally become more active and patrol their territory in search of food. The gray reef shark also shows strong site fidelity and may return to the same areas for several years.

A top predator in the food chain, the gray reef shark plays an essential role in maintaining the balance of coral reef ecosystems. Its diet mainly consists of bony reef fish, such as parrotfish, surgeonfish, and snappers. It also feeds on squid, octopuses, and various crustaceans, including crabs, shrimp, and lobsters.

An opportunistic hunter, it often takes advantage of fish aggregations and may hunt collectively with other sharks, increasing the pressure on prey, which then have greater difficulty escaping. Thanks to its speed, agility, and highly developed senses, it can easily detect the vibrations and scents released by its prey.

The gray reef shark is viviparous. Gestation lasts around twelve months, after which the female gives birth to a litter of one to six pups measuring between 18 and 24 inches in length. From birth, young sharks are fully independent and move into shallow or sheltered reef areas where they are better protected from larger predators.

The gray reef shark is listed as many other marine species within The IUCN Red List of threatened species. The gray reef shark appears in the IUCN Red List since 2020 within the category Endangered !