Distribution and habitat
The whale shark inhabits most tropical and warm-temperate seas. The fish is generally pelagic, living in the available sea but not in the better 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| Seasonal feeding aggregations occur in several coastal sites including the southern and eastern portions 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 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 State 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 Oman and Ing Hallaniyat islands in the Arabian Sea; and, very rarely, Eilat, Israel and Aqaba, The nike jordan. Although typically seen precisely what is, it has been found closer to area, entering lagoons or coral atolls, and near the lips of estuaries and waters. Its range is generally restricted to about 30° latitude. It really 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 kms (93 mi) off the shoreline of Karachi, Pakistan. The length of the specimen was considered 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 largest gatherings of whale fishes recorded.|22| Aggregations in that area are one of the most reliable seasonal gatherings known for whale sharks, with thousands and thousands occurring in most years among May and September. Linked ecotourism has grown rapidly to unsustainable levels.|23|
Neither mating nor pupping of whale sharks has been noticed.
The capture of a feminine in July 1996 that was pregnant with three hundred pups indicated whale fishes are ovoviviparous.|9||24||25| The eggs remain in the body and the females give birth to live youthful which are 40 to 62 cm (16 to 24 in) long. Evidence implies the pups are not almost all born at once, but rather the female retains sperm from one pairing and produces a steady stream of pups over a continuous period.|26| They will reach sexual maturity for around 30 years and their life is an estimated 70|9| to 100 years.|27|
On 7 March 2009, marine scientists in the Dubai 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, Israel, and was released into the outdoors. Based on this discovery, a few scientists no longer believe this area 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, fish eggs, Christmas Island red crab larvae |30| and small nektonic life, such as small squid or fish. It also provides nourishment to on clouds of ova during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no position in feeding. Feeding comes about either by ram filtering, in which the animal opens their mouth and swims forward, pushing water and meals into the mouth, or by energetic suction feeding, in which the creature opens and closes its mouth, sucking in quantities of water that are in that case expelled through the gills. In both cases, the filtration pads serve to separate meals from water. These exceptional, black sieve-like structures happen to 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 filtration pad surface, not perpendicularly through it, before driving to the outside, while denser food particles continue to the back of the throat.|32| This is certainly an extremely efficient filtration technique that minimizes fouling in 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 reproduce.
2019-02-12 14:01:01 * 2019-02-11 12:42:30
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