Species point records from 1970 Ridley north-west Scotland sublittoral photographic survey

Gordon Ridley is a lecturer is photography at Glasgow University and also a professional underwater photographer. It was felt that it would be of value for the NCC to analyse his considerable underwater slide collection pertaining to north-west Scotland. the area for which slides were investigated is from Loch Fyne, near Inverary (NR 9080) in the south, to Whiten Head, east of Cape Wrath (NC 500 686) in the north and extends as far west as St Kilda. Slides from 16 sites were investigated, some 534 slides in total. Copies were made for the NCC. The species present at each site are summarised in tabular form with detailed annotated species lists in seperate tables. In these lists details of substratum, abundance and association with other species is given. A general description of each site in terms of habitats and communities present is given where enough slides were available. It was possible to get a good idea of the main features of each site and the species present. Of particular interest was the occurrence of a distinctive community - the Dendrodoa grossularia/Clathrina coriacea community - present at/near Cape Wrath. Another recognisable community that occurs in sounds exposed to very strong tidal streams is the Tubularia indivisa - Halichondria panicea community. Some photographs from St Kilda show large areas of sloping rock covered by T. indivisa and a yellow encrusting sponge that cannot be identified from the slides. Species of particular interest were Parazoanthus anguicomus recorded at St Kilda and Whiten Head, which although not rare is occasionally recorded around Scotland and Protanthea simplex only recently discovered in Great Britain, but now with several records from the coast of west Scotland. Records currently considered sensitive have been removed from this dataset.