SAVIEZ-VOUS?                       << retour

WHALE SHARK

The species was first identified in April 1828 following the harpooning of a 4.6 Meter (15.1 ft) specimen in Table Bay, South Africa. It was described the following year by Andrew Smith, a military doctor associated with British troops stationed in Cape Town, He proceeded to publish a more detailed description of the species in 1892. The name "whale shark" comes from the fish's physiology; that is, a shark as large as a Whale that shares a similar filter feeder eating mode.


LOCATION FOUND
 

Kingdom: Animalia
Phylum: Chordata
Class: Chordrichthyes
Subclass: Elasombranchii
Order: Oretolbiformes
Family: Rhincodontidae
(Muller and Henle, 1893) Genus: Rhincodon
Smith, 1829 Species: R. typus

As a Filter Feeder, it has a capacious mouth which can be up to 1.5 metres (4.9 ft) wide and can contain between 300-350 rows of tiny teeth.As a filter feeder, it has a capacious mouth which can be up to 1.5 metres (4.9 ft) wide and can contain between 300-350 rows of tiny teeth. It has five large pairs of gills. 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 to each whale shark and because of this they can be used to identify each animal and hence make an accurate population count. Its skin can be up to 10 centemeters (3.9 in) thick. The shark has two pairs each of dorsal fins, and pectoral finsA juvenile whale shark's tail has a larger upper fin than lower fin while the adult tail becomes semi-lunate (or crescent-shaped). The whale shark's spiracles are just behind the eyes

The whale shark is not an efficient swimmer since the entire body is used for swimming, which is unusual for fish and contributes to an average speed of only around 5 kilometres per hour. The largest specimen regarded as accurately recorded was caught on Nov/11 1947 near the island of Baba, not far from Karachi, Pakistan It was 12.65 metres (41.5 ft) long, weighed more than 21.5 tonnes (47,300 lb), and had a girth of 7 metres (23 ft).(5) Stories exist of vastly larger specimens - quoted lengths of 18 metres (59 ft) are not uncommon in the popular shark literature - but no scientific records exist to support their existence. In 1868 the Irish natural scientist E. Perceval Wright spent time in the Seychelles,, during which he managed to obtain several small whale shark specimens, but claimed to have observed specimens in excess of 15 metres (49.2 ft), and tells of reports of specimens surpassing 21 metres (68.9 ft).