We now know that the blue whale is the largest sea creature, but it is not a fish. It is a mammal. So, you might ask -which is the biggest fish in the ocean? The answer is the ‘whale shark’. You might further ask – is it a whale or a shark? To answer, the whale shark is not a whale, but a shark. However, owing to its massive size (it is known to reach lengths of more than 12 metres), it has earned the name ‘whale’ shark.
Like many whales and unlike most sharks, it is a filter feeder. In another deviation from sharks, its mouth is located at the front of its head rather than on the underside of its head. However, like all true sharks it breathes with the help of gills, unlike whales which breathe air like humans do. Also, as with all sharks, its skeleton is made of cartilage.
Larger whale sharks may weigh up to 54,400 kg. It would follow that such enormous sharks would be top predators in the ocean, but the whale shark is a harmless fish. It feeds on tiny organisms called plankton that float in the ocean. It uses its massive mouth, which can stretch up to 1 metre wide; to take in the plankton-rich waters using sieve-like structures called filter pads to separate the food from water.
Picture Credit : Google