Though mostly seen offshore, some whales travel closer to the coasts through coral reefs and lagoons, or close to the mouths of estuaries. Mexico seems to be one of the more reliable locations to find this species, and the Atlantic Mexican population is unique compared to other known populations because of its high concentration and variety in size of its members. Though primarily considered to be pelagic, whale sharks are found at several coastal feeding sites, including Australia’s Ningaloo Reef, Zanzibar and Pemba in Tanzania, Utila in Honduras and Donsol and Batangas provinces in the Philippines. In the Atlantic Ocean, they range from New York to Brazil and from Senegal to Gabon past the Gulf of Guinea. They are found from California to Chile, off the coast of Hawaii and from Japan to Australia in the Pacific Ocean. As a result, whale sharks occur throughout the Indian Ocean. This species generally lives between latitudes 30°N and 35°S, in bodies of water with surface seawater temperatures between 69☏ and 77☏. Whale sharks have a wide distribution and are found in every warm-temperate and tropical sea except the Mediterranean. However, the teeth appear to play no role in feeding and are, thus, of little use to the sharks. As a filter feeder, the whale shark has a capacious mouth, which can measure up to 5 feet wide and contain 300 to 350 rows of tiny teeth, with a total of about 3,000 denticles or toothlike structures. The name “whale shark” is derived from the fish’s physiology-a shark as large as a whale that also shares similar filter feeder characteristics. Another possibility is that their coloration is an adaption to protect them from the sun’s ultraviolet radiation, since whale sharks frequently feed at the ocean surface. Also, these pigmented patterns may be connected to social behaviors, used for individual recognition and postural displays during courtship. For the sharks, this pattern of lines and spots enables them to “blend” into their surroundings, making them less conspicuous in their oceanic environment. These unique markings allow scientists to identify and track individual whale sharks in the wild. Its coloration ranges from gray to brown with rows of white spots amid pale horizontal and vertical lines. The whale shark’s skin can be up to 4 inches thick, and it has a creamy white underbelly. This two-lobed tail is crescent-shaped in adults, while juveniles have a considerably longer upper fin. The whale shark’s two dorsal fins-a large dorsal followed by a small one-are set toward the back of the body, which ends with a caudal fin. It has five large pairs of gills that filter food and water. The mouth is transverse, extremely wide and toward the front of its blunt snout. Its streamlined body and depressed, broad and flattened head distinguish it from other sharks. As with most shark species, female whale sharks are larger than males. The average size of an adult whale shark is between 11 and 20 tons with a length of 20 to 40 feet. The distinctively marked whale shark is the world’s largest living fish and is the only surviving species in family Rhincodontidae. The largest whale shark ever recorded with certainty was near Baba Island, Pakistan, in 1947, weighing approximately 21.5 tons and reaching a length of 41.5 feet. However, no reliable documentation exists of these claims. One piece of fish lore tells of the Maurguani, a vessel sailing the South Pacific in 1934, which rammed into a whale shark and splayed its 55-foot-long body across the prow of the ship. Perceval Wright of sighting 69-feet-long whale sharks at sea. Smith guessed that the shark must have weighed at least 37 tons and measured 56 feet in length, and there were even reports from 19th-century scientists such as E. Entangled in a bamboo fish trap, the massive shark was too heavy to drag ashore. Smith published an article describing an enormous whale shark that had been caught off the coast of Thailand in 1919. Since that time, stories of these massive creatures have found their place within history, as well as in fish lore. Yet there is no human record of the whale shark until 1828, when it was described and named by Andrew Smith, following the harpooning of a 15-foot-long specimen in Table Bay, South Africa. Modern sharks began to appear between 100 million and 65 million years ago-their ancestry dating back to the Jurassic and Cretaceous periods.
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