Echinoderms are quite common and include crinoids (feather stars) starfish and sea urchins.
Sea Urchins play an important role in grazing over large boulders, leaving the pink corraline algae. These areas are known as Barrens Habitat and allowing some gastropods to graze on newly settled algae and allow the growth of various sponges and ascidians.
Sea urchins are more active at night and can get quite old with some of the larger ones (test diameter 100mm) being as old as 15 years.
