What makes a fish a fish? These swimming vertebrates all seem to have fins and gills, but not always in the same place or the same skin type, in fact, there are well over 25,000 species of fish all over the world and the list is always growing. From that list there are some fish that are fast, some that are small and some that are so big they eat all the other fish in the sea! These are the ten biggest fishes and their average fully-grown body weights...
The Top 10 Heaviest Living Fish From Around the World10 - Reef manta ray - Average mass: 1.4 Tonnes
This might be the first Ray on this list, but it's certainly not the last of them. Growing up to 11 ft wide they certainly spread their weight out and looks strangely peaceful and graceful in the subtropical waters it hangs out in.
9 - Beluga sturgeon - Average mass: 1.57 Tonnes
Just when you started to think River Monsters were not a real thing, along comes a giant sturgeon to prove you wrong. While most people know them as "beluga whales" they are indeed just a fish and one that is often hunted for its eggs.
8 - Hoodwinker sunfish - Average mass: 1.87 Tonnes
Believe it or not, this giant fish was only first discovered in 2017!!! Known to be yet another type of Mola fish it just goes to show that anything could still be out there in our seas and oceans.
7 - Sharptail mola - Average mass: 2 Tonnes
If it looks familiar its because it too is a Mola (half-fish shape) species of fish much like the Ocean sunfish. The biggest difference is the Sharptail mola has a small tale and the Ocean sunfish doesn't.
6 - Ocean sunfish - Average mass: 2.3 Tonnes
Said to be the heaviest bony fish in the world they are often as tall as they are wide, mostly wishing to eat jellyfish as they swim past them. Despite their gigantic size, they are no threat to humans and most other fish unless they get too near their mouths.
5 - Giant oceanic manta ray - Average mass: 3 Tonnes
It is, of course, the largest Ray fish in the world and can grow up to 23 ft wide! That super flat, streamlined body helps them to travel all over the world and are known to travel thousands of miles.
4 - Tiger shark - Average mass: 3.11 Tonnes
The 'Giant Sea Tiger' gets its name thanks to its tiger stripes pattern going down its skin which does kind of resemble the stripes of a tiger. It is also known to kill more humans each year than all the species of Tigers known to man.
3 - Great white shark - Average mass: 3.32 Tonnes
If you have seen the film "Jaws" by Steven Spielberg you will know all about this shark. Sure, it doesn't go out of its way to eat us, humans, like it did in the film, but it has been known to do so.
2 - Basking shark - Average mass: 19 Tonnes
It might be one giant shark, but it mostly eats plankton which makes it one of only 3 plankton-eating sharks in the world. It gets its name from the way it is often seen feeding on the surface of the water as if it is basking in the sunlight, much like us humans do on the worlds most amazing beaches.
1 - Whale shark - Average mass: 21.5 Tonnes
It might not be the fastest of sharks, but this beast of a fish is said to have been around since 60 million years ago so its as close to being a living dinosaur and you are ever likely to get.
