The Sea Hare is a small sea creature that is often referred to as a ‘sea slug’. It can be found around many coasts of England where there is shallow water and sometimes it can be found in rock pools. It has tentacle-like organs on the rear end of its body that look similar to the ears of a hare and this is why it has the name ‘Sea Hare’. It is a ‘gastropod’ mollusc, like snails and slugs, and unlike a snail that has an external shell, the Sea Hare has an internal shell that can be seen through a hole in the Sea Hare’s body.
The Sea Hare can grow to twenty centimetres in length, although it usually averages around seven centimetres. It has a lumpy-looking body which can be olive, green, red or purple-black with grey-white mottling and blackish spots. It has two small tentacles on the front of its head and one flat broad tentacle on either side of its mouth. The tentacle–like organs at the rear of the Sea Hare’s body are used to eject a purple dye. This dye is ejected when the Sea Hare feels threatened or alarmed.
Sea Hares lay their eggs in masses of string-like gelatine which are attached to rocks, stones and sea lettuce. The larvae hatch out directly into the sea where they become part of zooplankton for around a month before settling on the seabed to develop into adult Sea Hares.