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The whale shark (Rhincodon typus) is a distinctively-marked member of the subclass Elasmobranchii of the class Chondrichthyes. It is the largest shark and also the largest living fish.


 


Record Holder: The greatest size accurately recorded was 12 meters (39 ft) long, with unofficial accounts of 18 meters (59 ft). It is not to be confused with the Basking shark (Cetorhinus maximus), the second largest fish.

Big Mouth: A member of the order Orectolobiformes, it is a filter feeder. The shark has a capacious mouth which can be up to 1.5m (5 ft) wide and contain up to 300 rows of tiny teeth.

Flat Head: As part of its feeding process, it also has five large pairs of gill arches. Two small eyes are located towards the front of the shark's wide, flat head.

The body is mostly grey with a white belly; three prominent ridges run along each side of the animal and the skin is marked with a 'checkerboard' of pale yellow spots and stripes. These spots are unique with every whale shark. Because of the spots uniqueness they can be used to mark each animal and make an accurate population count. But so far the whale sharks have not been fully and accurately counted. Its skin can be up to 10 cm thick.

Slow Swimmer: The shark has two pairs each of dorsal fins and pectoral fins. A juvenile whale shark's tail has a greater top fin than lower fin while the adult tail becomes semi-lunate, or crescent-shaped. The shark's spiracles are just behind the eyes. The whale shark is not an efficient swimmer; the entire body is in motion while the animal swims. The result of this motion, one that is very unusual for sharks, is an average speed of around 5 km/h.


On the Menu: The whale shark feeds on phytoplankton, macro-algae, plankton, krill or nektonic life (small squid or vertebrates). The many rows of teeth play no role in feeding, instead, water is actively drawn into the mouth and is passed over gill rakers and then out through the gill arches. Any material caught in the rakers is swallowed. The sharks, however, are active feeders and target concentrations of plankton or fish by olfactory cues rather than simply 'vacuuming' constantly. According to sailors, whale sharks congregate at reefs off the Belizean Caribbean coast, supplementing their ordinary diet by feeding on the roe of giant cubera snappers, which spawn in these waters in May, June and July, and between the full and quarter moons of these months.

Gentle Shark: When it is explained that most sharks are not dangerous to humans, this species is used as the leading example. Divers and snorkelers can swim around the giant fish without any problems.

Where in the World: The shark is often seen in Thailand, the Maldives, the Red Sea, Western Australia (Ningaloo reef), Gladden Spit Marine Reserve in Belize, and at the Galapagos islands. They are regularly seen from December to May in the Philippines (Donsol). Lucky divers have also come across whale sharks in the Seychelles and in Puerto Rico. Between December and September, they are well known to swim along the bay of La Paz in the mexican Baja California.


Birds and Bees: Like most sharks, the reproductive habits of the whale shark are obscure. Based on the study of a single egg recovered off the coast of Mexico in 1956, it was believed to be oviparous, but the capture of a pregnant female in July 1996 containing 300 young whale sharks indicates that they are viviparous with ovoviviparous development. The eggs remain in the body and the females give birth to live 40 to 60 cm young. It is believed that they reach sexual maturity at around 30 years and the life span has been estimated to be between 60 and 150 years.

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 Kingdom: Animalia

 Phylum: Chordata

 Class: Chondrichthyes

 Order: Orectolobiformes

 Family: Rhincodontidae

 Genus: Rhincodon

 Species: Typus