Ocean Sunfish (Mola Mola)

What to look for

The Mola mola is strange. It looks like a giant, floating head without a tail. These fish grow into huge discs. Most divers see individuals between 1.5 m and 3 m wide. I remember seeing one in 2016 that was nearly 4 m across.

Look for the thick skin. It appears grey or silver under the water. You might also see small remoras attached to their sides. They often hover near the surface. This is where they bask in the sun.

Behaviour you’ll observe

They move slowly. These fish use their dorsal and anal fins to propel themselves through the water column. Because they are ectothermic, they often swim upward to warm their bodies after deep feeding dives. You will see them lying on their sides.

This basking behaviour is common. They stay near the surface for long periods. Sometimes they look quite clumsy. However, they are very efficient at finding jellyfish.

Where and when

Timing is everything here. You should plan trips for July, August, September, or October. Sightings depend on water temperature and currents. At Sail Rock, I found the sighting probability is roughly 1 in 12 dives during peak months.

Another great spot is Manta Point Nusa Penida. The currents there can be very strong. You must be a confident diver to see them there. I once saw a group of three Mola mola near the surface at 12 m depth in August 2019.

Finding them is not guaranteed. Even in peak season, you might go 15 dives without a single sighting. The fish move with the seasonal thermoclines. They prefer the cooler water found during these specific months.

Diver etiquette

Do not chase them. These animals are slow and easily stressed by fast movement. Keep a distance of at least 3 m at all times. If you swim too close, they will dive deep.

Never touch the skin. Their skin is thick but sensitive to human oils. I saw a diver try to grab one in Bali once. It was a mistake because the fish immediately fled into the blue.

Watch your buoyancy. Avoid kicking up sand near them. Stay horizontal in the water column. This makes you less threatening to the fish.

Conservation status

The IUCN Red List classifies Mola mola as Vulnerable. This status reflects their declining numbers globally. They face many threats from commercial fishing. Bycatch is a major problem for this species.

Ocean warming also affects them. Changing temperatures shift where they feed. We need to protect their habitats to ensure they survive. Many regional fisheries are now tracking these incidents.

Summary of facts

| Feature | Detail | | :--- | : | | Average Size | 1.5 m - 3 m | | Best Months | July - October | | Danger Level | None | | IUCN Status | Vulnerable |

Check your local dive logs before booking. If you want the best chance, book a liveaboard for the Similan Islands in August.