THE world’s largest fish, whale sharks (Rhincodon typus) can reach lengths of 12m and weigh up to 21 tonnes. Although massive, they are docile and harmless to humans; they feed on tiny marine animals, including plankton, squid, crustaceans and schooling small fishes.
Whale sharks populate tropical and warm temperate seas, inhabiting both deep and shallow coastal waters and the lagoons of coral atolls. Electronic and satellite tagging of whale sharks have found that they can dive to depths of 700m and take long-distance migrations that can last years.