Diving with Mola Molas (aka Oceanic Sunfish)

The Mola Mola is also known as the Oceanic Sunfish and is one of the most unusual looking creatures in the sea.  Sunfish are often seen at the surface, so are sometimes mistaken for sharks due to their large dorsal fin. The oceanic sunfish is quite a docile, harmless fish. You will not encounter any problems diving with it. Although oceanic sunfish are usually shy creatures, they have been known to get used to divers at certain dive sites and can be curious, often approaching divers.

The Mola Mola is the heaviest of all bony fish. They can reach up to 3.2m with an average weight of 1,000kg. They generally eat jellyfish, complemented by squid, crustaceans, eel grass, fish larvae, small fishes, zooplankton and comb jellies. The nutritional value of these snacks is quite low, that is why oceanic sunfish eat a huge amount of food. 

They are found in temperate and tropical oceans around the world usually in oceanic waters, but they sometimes come inshore and are frequently seen basking in the sun near the surface. Researchers believe that even though they are mostly seen at the surface the Mola Mola spend a large portion of their time deeper than 200m. Early research suggests that individuals have been recorded swimming 26km in a day at a top speed of 3.2 km/h. 

Prolonged exposure to temperatures lower than 12°C can be dangerous for the fish, leading to death. One theory of why they sun themselves is for the purposes of a thermal recharge after diving to the cold depths of the ocean. 

Humans prey on Mola Mola for its neurotoxins which are considered a culinary delight in Asia, but in the European Union, the meat is banned. Certain parts of the fish are also used in traditional Chinese medicine. Moreover, they are frequently hit by boats and can suffocate on sea trash, like plastic bags, which look like jellyfish. Nevertheless, their population is considered stable.

More detailed information about Molla Molas/Ocean Sunfish can be found here.