Photographic Quantitative Sampling of Hard-Bottom Benthic Communities

Underwater 35 mm color photography was evaluated as a quantitative sampling technique for hard-bottom benthic community composition. Best results required artificial lighting and a reflex viewing system. Transparencies were best analyzed by random point sampling using a dissecting microscope and acetate overlays. Cover was a valuable community parameter that could be accurately and precisely quantified, computerized, and statistically treated. Photographic quadrat sampling was more practical, rapid, inexpensive, and provided more information than direct observation or hand-collected biomass samples. The accuracy of using cover to estimate biomass or numbers of individuals varied. Photographic sampling did not disturb the organisms present and provided convenient permanent records.