Sunfish spotted off Cornwall


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An aerial survey of marine life has revealed the presence of numerous giant Oceanic sunfish living off the coast of Cornwall in south west England.

A total of 19 of the fish were spotted in just two hours of flying over the Cornish coast. The Oceanic sunfish, Mola mola, is the world's largest bony fish species and can reach a length of 3m/10' and weigh up to two tonnes.

They are found around the world in water ranging from 12-25°C and are an occasional summer visitor to British shores. Sunfish are usually spotted at the water surface during the summer, when they lay on their sides and feed on jellyfish.

According to a report at, the aerial survey was undertaken by scientists from the School of Biosciences at the University of Exeter, the Marine Conservation Society and the Cornwall Wildlife Trust.

Dr Brendan Godley, senior lecturer at the University of Exeter Cornwall Campus, told "This sudden influx of these beautiful, giant fish was a fantastic surprise.

"We only spotted the sunfish lying on their side at the surface so there may have been more below the waves.

"This is the first time we have spotted them during our surveys, and we think they have arrived here in order to take advantage of anticipated jellyfish blooms as the summer sea temperatures rise."

Sunfish often drift at the surface with their large dorsal and anal fins flapping, however, they are also seen cruising in an upright position when not feeding.

They lack a tail fin and instead possess a small stump called a clavus, which acts rather like a rudder. Their dorsal and anal fins are flapped synchronously to propel the fish.

The species is listed in the Guiness Book of Records as the heaviest bony fish, as well as the fish species that produces the greatest number of eggs.

The Mola genus contains just two species: the Oceanic sunfish, Mola mola, and the Southern sunfish, Mola ramseyi, which occurs in the southern Atlantic and south west Pacific. The fish are members of the Tetraodontiformes Order, which also includes pufferfishes and triggers. Molids share the same sort of fused-beak mouth seen in other tetraodontiform fishes.