Whale Shark

The whale shark Rhincodon typus is the largest fish in the sea. It grows to over 12 m (40 ft) long, has a horizontal, slit-like mouth up to 1.5 m (5 ft) wide, and possesses a liver weighing up to a tonne. Its anterior dorsal fin can be up to 1.2 m (4 ft) tall, and its tail, with upper and lower lobes of similar size, can be enormous, up to 3 m (10 ft) from top to bottom.

The whale shark is not only big but also very conspicuous. Its markings--a brown-coloured skin with white spots and stripes--are easily recognised, and each individual has its own distinctive pattern. The mouth is at the front of the broad head, rather than being underslung. The eyes are remarkably small for such a large animal and the shark is able to roll them back into the eye socket for protection.

The skin on a whale shark's back is 10 cm (4 in) thick and very tough. Harpoons, buck-shot or rifle bullets just bounce of the whale shark, making it invulnerable to just about anything except a ship. Like the baleen whales, after which the species takes its common name, the whale shark is a filter feeder, straining out plankton, krill, squid and small fishes, such as anchovies and sardines, from the seawater.