What's the biggest fish in the sea? There are some that weigh several tons! The biggest creature in the ocean isn't actually a fish, but a whale. In fact, the blue whale is not only the biggest species in the sea but in the entire world! The average size of the blue whale is 242,500 pounds and 79 feet long. Imagine an animal weighing more than 121 tons! This infographic from SI Yachts shows the 75 largest underwater species in the world, all ranked by their average size.
Other massive underwater species within the top ten include the right whale (132,300 pounds and 51 feet), the bowhead whale (120,200 pounds and 49 feet), the humpback whale (63,900 pounds and 44 feet), and the whale shark (41,000 pounds and 48 feet). Even the "smaller" species, due to their ranking, can be massive. The mekong giant catfish, for example, weighs 385 pounds on average!