045 Out on the Causeway – The distribution of seashore invertebrates and seaweed is influenced by the cracks and hollows on the surface of the rock. Barnacles encrust most of the surface area with juvenile mussels and tiny limpets occupying small rounded bio-erosion hollows (about 1 centimetre diameter) liberally and almost regularly spread over the limestone. The low growth of algae seems almost lined up against a boundary imposed by a straight rock crack.
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