Whale Shark
Credit: Brian J. Skerry

History

In 1828, the first whale shark specimen known to science was discovered off the South African coast. It was later that year that Dr Andrew Smith, the leader of their discovery, had associated them with this remarkable name and declared them as the largest living shark species in the ocean.

The whale shark, Scientificly known as the Rhincodon Typus, is not a whale. The ancestry of this shark belongs to the Jurassic periods when the first present shark groups began to appear (around 200 million years ago).

The spicies is rare. The total number of confirmed reports of the whale shark did not pass 350 prior to the year 1985. However, in the interim, a lucrative ocotourism industry is established at the Western Australian northwest coast revolving around their annual appearance in the area.

Whale Shark in clear waters
Credit: Wikipedia

Biology and Ecoloy

Whale Sharks are close relatives of the bottom-dwelling sharks, scientificly known as the Orectolobiforms. The pattern of lines and spots covering the fish's body enables it to blend and males it less conspicuous in their oceanic environment. The particular pattern is stable over time and therefore capable to be used as an identity card.

 The fish is known to be a filter-feeding shark, one of three to be precise. The other two are the basketing and megamouth sharks, the basketing being the world's second largest fish.

The whale shark is able to open its mouth to a width greater than 1 meter to enhance the income. Mostly, it feeds on minute organisms. These relatively small creatures cover krill, crabe larvae and jellyfish. 

Morever, these creatures are able to feed via vertical suction. Joined to sihting data, informations of feeding behaviour are more likely to help researchers understand the basic relationship between the creature's appearance and the natural marine events.

 

Distribution

Australia is the most raliable location to find the world's largest fish. However, regural sightings have been recorded from several regions such as India, South Africa, Mexico and Indonesia. The species tend to prefer surface sea-water temperatures between 21-25 °C along with latitudes between 30°N and 35°S.

Whale Shark in Honduras seas
Credit: http://diving.abyss.com.au/wp-content/uploads/2012/02/Whale-Shark-Honduras.jpg

Breeding

Male sharks can be distinguished by the presence of two claspers near the pelvi fin which are absent in the female organism. Only a single pregnant whale shark has been recorded and the species' actual breedin area remains unknown.