The world largest animal ( fish) , whale sharks is at the verge of in extinct. According to the journal Biological Conservation. Marine biologists estimate the number of humpbacks worldwide have grown more than 40,000 adults.

Blue Whale which is 33 metres in length is also considered to be the largest animal to be existed. They whales have been hunted for more than 40 years by the whalers. Whereas, the sperm whales are a deep diving species and around 2.5 to 3.5 metres (9-11 feet) in length, and weighing 350-500 kilograms

The study by the Australian scientist , also analyses that Ningaloo Reef, in Western Australia. The place which is the tourist spot to view the whale sharks.

The whale shark is not only fewer down in numbers but also shrinked down by the size. The total lengths of whale sharks decreased by 1.6 metres. The actual length is 15 m to 18 m and can weigh more than 10 tons. The feed on anchovies and planktons.

The whale sharks can be often seen with the divers in Thailand, the Philippines, and Western Australia. They are known to be the “the world’s tropical and warm-temperate ocean”.