Distribution and habitat
The whale shark inhabits all tropical and warm-temperate waters. The fish is generally pelagic, living in the open sea but not in the greater depths of the ocean, though it is known to occasionally dive to depths of as much as one particular, 800 metres (5, 900 ft).|17| Temporary feeding aggregations occur at several coastal sites including the southern and eastern portions of South Africa; Saint Helena Isle in the South Atlantic Sea; 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 Thailand; 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, Philippines; Nosy Be in Madagascar; away Tofo Beach near Inhambane in Mozambique; the Tanzanian islands of Mafia, Pemba, Zanzibar; Gulf of Tadjoura in Djibouti, the Advertising Dimaniyat Islands in the Gulf of Oman and Ing Hallaniyat islands in the Arabian Sea; and, very rarely, Eilat, Israel and Aqaba, Jordan. Although typically seen just offshore, it has been found closer to terrain, entering lagoons or coral reefs atolls, and near the lips of estuaries and waters. Its range is generally limited to about 30° latitude. It can be 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 kms (93 mi) off the coast of Karachi, Pakistan. The length of the specimen was said 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 most significant gatherings of whale sharks recorded.|22| Aggregations in that area are among the most reliable seasonal gatherings reputed for whale sharks, with huge numbers occurring in most years between May and September. Affiliated ecotourism has grown rapidly to unsustainable levels.|23|
None mating nor pupping of whale sharks has been observed.
The capture of a feminine 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 adolescent which are 40 to sixty cm (16 to 24 in) long. Evidence signifies the pups are not most born at once, but rather the feminine retains sperm from one mating and produces a steady stream of pups over a lengthened period.|26| They 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 Thailand discovered what is believed to be the tiniest living specimen of the whale shark. The young shark, measuring only 38 centimeter (15 in), was observed with its tail tied to a stake at a seashore in Pilar, Sorsogon, Philippines, and was released into the wild. Based on this discovery, some scientists no longer believe this area is just a feeding ground; this web site may be a birthing ground, as well. Both young whale sharks and pregnant females have been seen in the marine environments of Saint Helena in the South Atlantic Ocean, wherever numerous whale sharks can be spotted during the summer.
The whale shark is a filtration system 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, fish eggs, Christmas Island reddish colored crab larvae |30| and small nektonic life, such as small squid or fish. It also nourishes on clouds of eggs during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no part in feeding. Feeding happens either by ram filtering, in which the animal opens its mouth and swims onward, pushing water and meals into the mouth, or by effective suction feeding, in which the canine opens and closes its mouth, sucking in volumes of water that are then simply expelled through the gills. In both cases, the filtration system 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 travels nearly parallel to the filter pad surface, not perpendicularly through it, before passing to the outside, while denser food particles continue to the back with the throat.|32| This really is an extremely efficient filtration approach that minimizes fouling in the filter pad surface. Whale sharks have been observed "coughing", presumably to clear a build-up of particles from the filtration pads. Whale sharks move to feed and possibly to reproduce.
2019-01-26 23:41:36 * 2019-01-10 22:43:45
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