Photo copyright Tim Nicholson.
Sea Hares, Aplysia punctata
Taken on Bowes Rock off the Isle of Man
The sea hare has flaps of tissue on its back, thought to look like the ears of a hare. Herbivorous, the type of seaweed they eat may affect their colour - either red, brown or green. The above specimens have thus probably been eating red seaweeds. Like all sea slugs, the sea hare is a hermaphrodite. Unusually, though, any sea hare can fertilise any other. Several sea hares can form a mating chanin where each behaves as a male to the one below it, and a female to the one above.
Great British Marine Animals, by Paul Naylor, Deltor (2011)
The Underwater Photographer: Digital and Traditional Techniques, by by Martin Edge, Paperback, 536 pages (2009)