Sustainable dive ecotourism on a South African coral reef

SCUBA ecotourism provides economic support for local human communities and for conservation. Such support should be sustainable and as ecologically no n-destructive as possible to its coral reef foundation. In recent years, th e major increase in SCUBA activity has become a significant consideration a t some locations. Among these are the South African coral reefs at Sodwana Bay, which receive 80 000 dives per year. Between May 1998 and January 1999 , assessments using line-intercept and belt transects showed that 5.9% of h ard corals and 4.0% of soft corals were damaged from various causes, while only 0.02% of the hard corals were dead. Of the 222 diver contacts observed , only 1.63% produced instant and visually-clear damage, with no measurable decline in overall coral reef health. Direct observations on 89 recreation al divers showed that photographers made damaging contacts on nine out of t en dives, while novice divers made one such contact per six dives, moderate ly experienced divers about once every 14 dives, and very experienced diver s about once every 123 dives. Increased time lapsed since the last dive inc reased diver damage by novices. We calculated that the 80 000 dives were eq uivalent to 1 m(2) of reef receiving 2.3 diver contacts per year. Acropora austera was by far the most significantly damaged coral, with one out of fo ur branches broken per year. But as this species accounted for only 0.2% of reef benthos cover, this impact was not representative of overall reef hea lth. This heavy species-specific impact makes A. austera a good bio-monitor .