Distribution and habitat
The whale shark inhabits almost all tropical and warm-temperate waters. The fish is largely pelagic, living in the open up sea but not in the greater depths of the ocean, although it is known to occasionally dive to depths of as much as one particular, 800 metres (5, nine hundred ft).|17| Temporary feeding aggregations occur by several coastal sites like the southern and eastern portions of South Africa; Saint Helena Tropical isle in the South Atlantic Ocean; Gulf of Tadjoura in Djibouti, Gladden Spit in Belize; Ningaloo Reef in Western Australia; Kerala|18|, Lakshadweep, Gulf of Kutch and Saurashtra coast of Gujarat in India;|19| Útila in Honduras; Southern Leyte; Donsol, Pasacao and Batangas in the Korea; off Isla Mujeres and Isla Holbox in Yucatan and Bahía de los Ángeles in Baja California, México; Maamigili island, Maldives; Ujung Kulon National Park in Indonesia; Cenderawasih Bay Country wide Park in Nabire, Papua, Indonesia; Flores Island, Dalam negri; Nosy Be in Madagascar; off Tofo Beach near Inhambane in Mozambique; the Tanzanian islands of Mafia, Pemba, Zanzibar; Gulf of Tadjoura in Djibouti, the Ad Dimaniyat Islands in the Gulf of mexico of Oman and 's Hallaniyat islands in the Arabian Sea; and, very rarely, Eilat, Israel and Aqaba, Jordan. Although typically seen precisely what is, it has been found closer to land, entering lagoons or coral formations atolls, and near the teeth of estuaries and streams. Its range is generally limited to about 30° latitude. It is capable of diving to depths of at least 1, 286 m (4, 219 ft),|20| and is migratory.|9| On 7 February 2012, a large whale shark was found floating 150 kilometres (93 mi) off the coastline of Karachi, Pakistan. The size of the specimen was considered to be between 11 and doze m (36 and 39 ft), with a weight of around 15, 000 kg (33, 000 lb).|21|
In 2011, more than 400 whale sharks gathered off the Yucatan Coast. It was one of the greatest gatherings of whale sharks recorded.|22| Aggregations in that area are among the most reliable seasonal gatherings known for whale sharks, with large numbers occurring in most years between May and September. Affiliated ecotourism has grown rapidly to unsustainable levels.|23|
Neither mating nor pupping of whale sharks has been witnessed.
The capture of a woman in July 1996 that was pregnant with three hundred pups indicated whale sharks are ovoviviparous.|9||24||25| The ova remain in the body and the females give birth to live youthful which are 40 to 62 cm (16 to twenty-four in) long. Evidence signifies the pups are not every born at once, but rather the feminine retains sperm from one pairing and produces a steady stream of pups over a long term period.|26| They will reach sexual maturity by around 30 years and their life expectancy is an estimated 70|9| to 100 years.|27|
On 7 March 2009, marine scientists in the Israel discovered what is believed to be the tiniest living specimen of the whale shark. The young shark, measuring only 38 centimeter (15 in), was discovered with its tail tied to a stake at a shore in Pilar, Sorsogon, Korea, and was released into the untamed. Based on this discovery, a few scientists no longer believe this place is just a feeding ground; this site may be a birthing place, as well. Both young whale sharks and pregnant females have been seen in the seas of Saint Helena inside the South Atlantic Ocean, in which numerous whale sharks can be spotted during the summer.
The whale shark is a filtration feeder - one of simply three known filter-feeding shark species (along with the basking shark and the megamouth shark). It feeds on plankton including copepods, krill, seafood eggs, Christmas Island purple crab larvae |30| and small nektonic life, such as small squid or fish. It also passes on clouds of eggs during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no purpose in feeding. Feeding happens either by ram filtration, in which the animal opens its mouth and swims onward, pushing water and food into the mouth, or by productive suction feeding, in which the creature opens and closes its mouth, sucking in amounts of water that are therefore expelled through the gills. In both cases, the filtration pads serve to separate meals from water. These one of a kind, black sieve-like structures are presumed to be modified gill rakers. Food separation in whale sharks is by cross-flow filtration, in which the water trips nearly parallel to the filtration pad surface, not perpendicularly through it, before moving to the outside, while denser food particles continue to the back with the throat.|32| This is an extremely efficient filtration method that minimizes fouling of the filter pad surface. Whale sharks have been observed "coughing", presumably to clear a build-up of particles from the filter pads. Whale sharks migrate to feed and possibly to breed.
2019-02-14 5:41:30 * 2019-02-13 03:02:27
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