The sunfish is one of the impressive figures that you will be able to discover in the Grand Large experience.

Ocean Sunfish Mola mola

Identity card

Ocean Sunfish

Scientific name:
Mola mola
Year of description:
Linnaeus, 1758
IUCN Status:

It lives in tropical, subtropical and temperate waters around the world.


Pelagic (open sea).


50 cm up to more than 3 metres long. up to 2 tonnes


Jellyfish, salp, ctenophore, squid, small crustaceans

Ocean Sunfish

They are the biggest (and the heaviest too!) representative of bony fish.

And with very good reason!

Sunfish never stop growing: their growth depends directly on the animals they feed on. To put it in a nutshell, the more they eat the bigger they get.

Did you know ?

When sunfish drift on the surface soaking up the sunlight, they also makes the most of this to have their parasites removed by certain birds. This is because they are usually infested by some forty different species of parasites that they attempt to get rid of in various ways.

Where is the animal to be found?

The biggest bony fish in the world, it represents life on the high seas, both on the surface of the oceans and in their depths.

How can it be recognised?

The ocean sunfish, or Mola mola to give its Latin name, is a pelagic fish whose unusual silhouette is easily recognisable.

A laterally flattened oval body whose colour varies from a silvery grey to white, a protuberance on its head, very small pectoral fins, and dorsal and anal fins whose length can nearly double this fish’s height. Its caudal fin has disappeared during the course of its evolution to become an appendage called a clavus; this links the dorsal fin to the anal fin but does not help it to propel itself. It uses its dorsal and anal fins to advance.

Often swimming close to the surface of the sea, its dorsal fin can be confused with a shark’s fin. Indeed, ocean sunfish either swim upright with their dorsal fin protruding which gives them a sculling motion, or lying on their side drifting along with the current on the surface. It is likely that in the latter case it does this to restore its heat reserves. The sunfish owes its name to this. Curiously its French name- which translates into English as moonfish – comes from its round shape: at night its silhouette looks like the reflection of the Moon in the sea.

The sunfish does not have scales or a swim bladder.

What is distinctive about it?

  • Sunfish never stop growing: their growth depends directly on the animals they feed on. To put it in a nutshell, the more they eat the bigger they get.
  • It is thought that in the Mediterranean a 120-kg sunfish eats about 71 kg of jellyfish a day.
  • The increase in this fish’s population is perhaps linked to the phenomenon of jellification of the oceans, the term used to designate the proliferation of jellyfish no doubt promoted not only by climate change but also by the overfishing of the jellyfish’s predator species. Sunfish are inoffensive and do not have many predators.
  • The increase in the number of sunfish may also be related to the waning populations of sharks , one of this fish’s rare predators. 100 million: that’s the number of eggs that a sunfish can release in a single spawning, which make it the bony fish that spawns the most eggs. The eggs are released into the sea and fertilised by sperm. On hatching, the juveniles are only a few millimetres long and are covered with spines that disappear as they grow.

Threat and protective measure

They are the victim of drift nets and of the plastic bags they swallow because they confuse them with jellyfish.

Where can I find it at Nausicaá?


Ocean Sunfish mola mola

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