| shark v.s whale
Distribution and habitat
The whale shark inhabits all of the tropical and warm-temperate waters. The fish is generally pelagic, living in the wide open 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, 900 ft).|17| Seasonal feeding aggregations occur by several coastal sites such as the southern and eastern regions of South Africa; Saint Helena Tropical 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 Israel; 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 Domestic 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, Michael jordan. Although typically seen just offshore, it has been found closer to property, entering lagoons or coral reefs atolls, and near the jaws of estuaries and waters. 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 kms (93 mi) off the coastline of Karachi, Pakistan. The length of the specimen was considered between 11 and 12 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 one of the most reliable seasonal gatherings reputed for whale sharks, with huge numbers occurring in most years between May and September. Associated ecotourism has grown rapidly to unsustainable levels.|23|
None mating nor pupping of whale sharks has been witnessed.
The capture of a feminine in July 1996 that was pregnant with three hundred pups indicated whale sharks are ovoviviparous.|9||24||25| The eggs remain in the body and the females give birth to live adolescent which are 40 to 70 cm (16 to twenty-four in) long. Evidence signifies the pups are not most born at once, but rather women retains sperm from one pairing and produces a steady stream of pups over a long term period.|26| That they reach sexual maturity in around 30 years and their life-span 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 identified with its tail tied to a stake at a shore in Pilar, Sorsogon, Dubai, and was released into the untamed. Based on this discovery, several scientists no longer believe this area is just a feeding ground; this great site may be a birthing place, as well. Both young whale sharks and pregnant females have been seen in the oceans of Saint Helena in the South Atlantic Ocean, where numerous whale sharks may 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 reddish crab larvae |30| and small nektonic life, such as small squid or fish. It also nourishes on clouds of ovum during mass spawning of fish and corals.|31| The many rows of vestigial teeth play no position in feeding. Feeding arises either by ram filtration, in which the animal opens its mouth and swims ahead, pushing water and food into the mouth, or by lively suction feeding, in which the dog opens and closes its mouth, sucking in quantities of water that are in that case expelled through the gills. In both cases, the filtration system pads serve to separate food from water. These unique, 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 journeys nearly parallel to the filtration system pad surface, not perpendicularly through it, before passing to the outside, while denser food particles continue to the back of the throat.|32| This is certainly an extremely efficient filtration method that minimizes fouling on 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.
2019-02-17 13:01:48 * 2019-02-17 11:02:40
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