Sponges can be bright yellow like the prawn cracker sponge (Axinella infundibuliformis) to dark grey like the elephant's hide sponge (Pachymatisma johnstonia). These are fantastic underwater animals, bringing vibrant colour to the seabed. Sponges have no mouth but feed by pumping water through their bodies to filter food.
They can be seen all year round, both diving or snorkelling. Some of Europe's coastal destinations are particularly rich in this type of animals. For example, 130 species have been recorded in Rathlin Waters, including about a third of the total sponge fauna recorded in Britain and Ireland, and some not recorded elsewhere.