The Ocean Sunfish waves its large dorsal and anal fins to move itself, drifting through the open ocean. At almost 10 feet long and 14 feet tall, the sunfish is the largest bony fish on the planet, and yet it only appears like half a fish.
Nicknamed ‘the swimming head’, the sunfish’s peculiar morphology of a curved, truncated shape forms as their back fin never grows; it folds within itself as the sunfish develops, creating a rounded rudder called a clavus, which the sunfish uses to steer through the water.
Its appearance is also the inspiration for its latin name, with mola meaning ‘millstone’, due to the sunfish’s circular shape and stone-like skin. Their rough texture is caused by the tendency of this species to become highly infested with skin parasites. This explains some of the peculiarities of its behaviour, as often they are seen breaching the surface up to 10 feet, and splashing back down to shake off the parasites. In a similar fashion to many sharks and turtles, the sunfish allows smaller fish to pick at the parasites on its skin; a symbiotic relationship, in which both organisms benefit.
Being such slow-moving creatures, they feed on creatures that drift with the ocean currents. This includes jellyfish, plankton and algae, which they engulf in their small, beaked mouths that are unable to close completely.
The Mola mola truly are a beautiful species, and yet like all marine life they are threatened by human activity. With many suffocating on plastic which they mistake for jellyfish, or getting snagged in nets as they are clumsy swimmers, they are classified as vulnerable. To learn more about marine conservation and how you can help protect threatened species like the sunfish, follow the link to our video.
Watch more Deep Sea Wonders:
#1 The Greenland Shark – https://www.youtube.com/watch?v=XeOSlZYdvLY
#2 The Coelacanth – https://www.youtube.com/watch?v=__Woo6L1bl0&t=20s
#3 The Oarfish – https://www.youtube.com/watch?v=Baxnlt61jYc&t=25s
#4 The Ocean Sunfish – https://www.youtube.com/watch?v=e-FK1aR1pic&t=34s
#5 The Megamouth Shark – https://www.youtube.com/watch?v=uHhhDnksp44
#6 The Giant Squid – https://www.youtube.com/watch?v=f-y0TNNiZOs
Footage used:
https://www.youtube.com/watch?v=A1WBilMrDIU
https://www.youtube.com/watch?v=5SpxY5OLLxc
https://www.youtube.com/watch?v=91xefqzp4rY
https://www.youtube.com/watch?v=9dCke2RsKYQ
https://www.youtube.com/watch?v=hm7VlBrNDts
https://www.youtube.com/watch?v=juZat2dfg58
https://www.youtube.com/watch?v=U60obmWODLQ
Music used:
Interstellar – Ross Bugden (https://www.youtube.com/watch?v=_rbVt0z6NLM)
More information on this incredible fish:
https://www.nationalgeographic.com/animals/fish/o/ocean-sunfish/