Distribution Whale Shark | whale shark gills
Distribution and habitat
The whale shark inhabits all tropical and warm-temperate seas. The fish is mainly pelagic, living in the open sea but not in the higher depths of the ocean, even though it is known to occasionally dive to depths of as much as 1, 800 metres (5, nine hundred ft).|17| Temporary feeding aggregations occur for several coastal sites like the southern and eastern regions of South Africa; Saint Helena Tropical island 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 Philippines; 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 State Park in Nabire, Papua, Indonesia; Flores Island, Indonesia; Nosy Be in Madagascar; off Tofo Beach near Inhambane in Mozambique; the Tanzanian islands of Mafia, Pemba, Zanzibar; Gulf of Tadjoura in Djibouti, the Advertisement Dimaniyat Islands in the Gulf of mexico of Oman and 's Hallaniyat islands in the Arabian Sea; and, very rarely, Eilat, Israel and Aqaba, Test. Although typically seen precisely what is, it has been found closer to land, entering lagoons or coral atolls, and near the jaws of estuaries and waters. Its range is generally limited to about 30° latitude. It truly 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 seacoast of Karachi, Pakistan. The size of the specimen was said to be between 11 and 12 m (36 and 39 ft), with a weight of around 15, 000 kilogram (33, 000 lb).|21|
In 2011, more than 400 whale sharks gathered off the Yucatan Coast. It was one of the major gatherings of whale fishes recorded.|22| Aggregations in that area are one of the most reliable seasonal gatherings reputed for whale sharks, with good sized quantities occurring in most years among May and September. Affiliated ecotourism has grown rapidly to unsustainable levels.|23|
Not mating nor pupping of whale sharks has been witnessed.
The capture of a female in July 1996 that was pregnant with three hundred pups indicated whale fishes are ovoviviparous.|9||24||25| The ovum remain in the body and the females give birth to live youthful which are 40 to 70 cm (16 to 24 in) long. Evidence shows the pups are not almost all born at once, but rather women retains sperm from one mating and produces a steady stream of pups over a lengthened period.|26| They will reach sexual maturity for around 30 years and their lifetime 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 beach in Pilar, Sorsogon, Israel, and was released into the wild. Based on this discovery, several scientists no longer believe this area is just a feeding ground; this site may be a birthing surface, as well. Both young whale sharks and pregnant females have been seen in the waters of Saint Helena inside the South Atlantic Ocean, just where numerous whale sharks could be spotted during the summer.
The whale shark is a filter feeder - one of only 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 crimson crab larvae |30| and small nektonic life, such as small squid or fish. It also nourishes on clouds of ova during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no role in feeding. Feeding takes place either by ram purification, in which the animal opens their mouth and swims frontward, pushing water and meals into the mouth, or by lively suction feeding, in which the canine opens and closes their mouth, sucking in sizes of water that are after that expelled through the gills. In both cases, the filtration pads serve to separate foodstuff from water. These one of a kind, black sieve-like structures will be 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 filter pad surface, not perpendicularly through it, before passing to the outside, while denser food particles continue to the back from the throat.|32| This is certainly 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 move to feed and possibly to reproduce.
2019-02-02 16:41:28 * 2019-02-02 06:42:06
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