The Mola: One of the Strangest Fish

The Mola. What a cute name haha; it is derived from the Latin word mola which means millstone which refers to the mola's roundish shape. Also known as the ocean sunfish, the mola is the heaviest of the bony fishes, with large specimens reaching 14 ft (4.2m) vertically & 10 ft (3.1m) horizontally & weighing nearly 5000 pounds (2268kg). 

The mola looks like a huge fish head without a tail
Interesting facts:
  • They are found in temperate & tropical oceans around the globe.
  • Their shape is formed because their back fin simply never grows! It folds upon itself to form a rounded rudder called the clavus. 
  • They are frequently seen "lying on their side" basking under the sun: hence the common name "sunfish".

Sunbathing in horizontal position
  • They eat jellyfish. However since jellyfish isn't the most nutritional food in the world, they have to consume A LOT to maintain their huge bulk.
  • They are harmless to humans, although they have been known to be curious & will approach a human diver. Their dorsal fin are often mistaken for a shark's when it protudes above the water surface.

Big sushi...
  • They are frequently caught in fishing nets & have been known to suffocate when they consume plastic bags that often resemble jellyfish.
  • Skin on the clavus is smoother than that on the body, which can be as rough as sandpaper.
  • About 40 species of parasites reside externally & internally. In temperate climates, sunfishes tend to frequent kelp forest where cleaner wrasses will eat the parasites off the skin. In the tropics, fish from the reef carry out cleaner duties; sometimes sunfish will bask at the water surface to allow seabirds to feed on the parasites. Sunfishes sometimes breach more than 10 ft above the surface to dislodge parasites from their skin.
  • Predators include humans, orcas & sharks. Sea lions display bizarre behaviour: they rip off the fins of the sunfish, toss the helpless but still-alive fish in the air, then abandon the dismembered sunfish. The sunfish then sinks to the bottom where it is slowly consumed by starfishes.

Starfishes consuming dying mola
The mola is one of the most fascinating yet mysterious creatures of the ocean. If you're an avid diver or simply a very interested individual, consider helping out here to study mola populations using the NASA methodology for star patterning. You may like to browse here to learn more about the mola ;)


Anonymous said...

mola,nice name isn't it?freaking weird tho.when i 1st saw da 1st pic,i tot it only a size of a puffer fish but compared to da diver,it sure does big in size.wonder how the sunbathing looks like,such a big fish on the surface huh.

Rowan said...

I think we can lean on the fish & sunbath together...Haha what a picture!