Of the 4 shores surveyed, our conclusion is that they rank as follows in descending order of importance: i) Old Grimsby Zostera bed and Rushy Point, ii) Tresco Flats, iii) St Martin's Flats, iv) Samson Flats. Each of the 4 shores has a certain number of species in common, such as heart-urchins, terebellid worms, bivalves and burrowing anemones. Rushy Point, Tresco, has persistent scoured channels with dense populations of the burrowing anemone Cereus pedunculatus and, not far away, an area of highly sorted gravel with dense populations of the large topshell, Gibbula magus; just to its north, the Zostera bed in Old Grimsby Harbour has a rich and varied fauna not repeated elsewhere. Again, the Tresco Flats, on the other side of the island, have rich beds of the tube-dwelling polychaetes Amphitrite edwardsi and Chaetopterus variopedatus, and of the burrowing heart-urhcins Echinocardium and Spatangus. There is a case for recognising the importance of such unique shores by appropriate conservation measures, or at least by calling attention to them in publicity or 'nature trail' brochures somewhat less than others. Records currently considered sensitive have been removed from this dataset.
Habitat point records from 1982 University of Exeter Isles of Scilly littoral sediment survey