A simple, cheap, system has been designed and built which facilitates underwater stereophotography with a single Nikonos camera and standard lens. A monitoring station on the north-east coast of Skomer Island (Dyfed, Wales) with permanent sites at 10, 20 and 25 m below Chart Datum was established during the spring of 1982. The four sites have been stereophotographically sampled at intervals since July 1982. The epibenthic communities present at the sites are briefly described and major changes between 1982 and 1983 documented. The limitations of the stereophotographic system and other techniques employed are identified and recommendations made for improvements.
