It is fascinating that the largest animals living in the ocean are not fish but mammals, with the blue whale being the biggest of them all. An adult blue whale averages about 27 meters in length and weighs nearly 200 tons.
Among the largest marine animals in the world, there are as many as 17 species that belong to the class of mammals, while the rest are fish. Notably, included in the top 30 is one cephalopod species, the giant squid.
There are also other large species such as the Kaluga sturgeon, Amazonian river dolphin, and others, but these are not included as they are freshwater animals; this article will only list marine animals.
