Whale Shark Distribution | whale shark jumping out of water
Distribution and habitat
The whale shark inhabits most tropical and warm-temperate oceans. The fish is mainly pelagic, living in the open up sea but not in the increased depths of the ocean, though it is known to occasionally dive to depths of as much as one particular, 800 metres (5, nine hundred ft).|17| Periodic feeding aggregations occur at several coastal sites like the southern and eastern parts of South Africa; Saint Helena Island 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 Country specific Park in Nabire, Papua, Indonesia; Flores Island, Dalam negri; Nosy Be in Madagascar; away 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 Oman and Way Hallaniyat islands in the Arabian Sea; and, very rarely, Eilat, Israel and Aqaba, Test. Although typically seen overseas, it has been found closer to terrain, entering lagoons or coral formations atolls, and near the lips of estuaries and rivers. Its range is generally restricted to about 30° latitude. It is actually 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 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 major gatherings of whale fishes recorded.|22| Aggregations in that area are among the most reliable seasonal gatherings known for whale sharks, with large numbers occurring in most years among May and September. Linked ecotourism has grown rapidly to unsustainable levels.|23|
Not 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 fishes are ovoviviparous.|9||24||25| The ova remain in the body and the females give birth to live adolescent which are 40 to 62 cm (16 to twenty-four in) long. Evidence suggests the pups are not all born at once, but rather the feminine retains sperm from one pairing and produces a steady stream of pups over a extended period.|26| That they reach sexual maturity by around 30 years and their life-span is an estimated 70|9| to 100 years.|27|
On 7 March 2009, marine scientists in the Philippines discovered what is believed to be the tiniest living specimen of the whale shark. The young shark, measuring only 38 cm (15 in), was located with its tail tied to a stake at a seaside 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 great site may be a birthing surface, as well. Both young whale sharks and pregnant females have been seen in the oceans of Saint Helena in the South Atlantic Ocean, just where numerous whale sharks could be spotted during the summer.
The whale shark is a filtration feeder - one of just 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 eggs during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no function in feeding. Feeding comes about either by ram purification, in which the animal opens it is mouth and swims forwards, pushing water and food into the mouth, or by effective suction feeding, in which the creature opens and closes their mouth, sucking in volumes of prints of water that are then expelled through the gills. In both cases, the filtration system 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 moves nearly parallel to the filtration system pad surface, not perpendicularly through it, before driving to the outside, while denser food particles continue to the back in the throat.|32| This can be an extremely efficient filtration method 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 breed.
2019-01-10 15:49:40
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