Intertidal Habitats
  Rocky shores  

Rocky shores are relatively rare within the Sanctuary. Rock flats and mixed sand-rock habitats are much more common. Around the high tide level a tiny snail, a winkle (25), occurs in large numbers grazing on black algal mats which cover the rocks. It is possible to find the sea slater (31) sheltering under stones.


At a slightly lower level rocks are covered with the first of three barnacle species. These live in overlapping zones, each one at a lower level down the mid shore. In crevices it is possible to find the shells of the rock oyster (26), the cluster winkles and turban shells. Wherever loose stones occur the rock crab (29) is to be found.


The mid shore is often characterised by the blue-white tubes of a polychaete worm (28) and by numerous top shells. Here the carnivorous dog whelk (30) hunts its prey such as the top shells (27). On the lower mid shore, yellow-brown algae are common for the first time, together with hermit crabs scuttling about in their borrowed snail shells while porcelain crabs lurk under the rocks.


The lower shore is usually covered, except on spring tides, and often consists of mixed sand and boulders, forming the feeding grounds for the turnstone (36). On the surface of these rocks may grow bladder-like brown algae (34), especially in the winter. Their lower surfaces are covered with sea squirts and sponges (35). Sargassum (32) is also attached to the rocks at this level. The starfish crawl around feeding on small bivalves, sea slugs graze the algae and the blennies (33) hunt for suitable scraps of food.

  Some more pictures of animals living on rocky shores:  
Sea slug
Turban shells
Pearl oyster
Beach crab
Hermit crab
Rock crab