Effects of recreational SCUBA diving on fore-reef slope communities of coral reefs

This study investigated the effects of recreational SCUBA diving on the fore-reef slopes of coral reefs near Sharm-el-Sheikh, a popular resort in Egypt. Benthic communities were compared using randomly placed 1-m2 quadrats at three sites subdivided into heavily and little dived areas. There were significantly more damaged coral colonies, loose fragments of live coral, fragments of coral re-attached to the substratum, partially dead and abraded corals in areas heavily used by divers than in control areas. Damage to corals varied with growth form, branching forms being most vulnerable to breakage. Changes to communities at heavily and little dived sites were studied over 12 months using 3 × 3 m permanent quadrats. No significant increases in damage attributable to diving were detected for the three sites combined. However, when considered individually, the site which had experienced the greatest increase in diving appeared to have accumulated damage (broken coral) whereas the two others did not. For management purposes the results show that some reefs can sustain heavy levels of diving without apparent continued degradation. New dive sites can accumulate damage very rapidly. However, at the levels of diver use encountered during this study this may be more of an aesthetic than a biological problem. © 1992.