In Coral Reef ecosystems, The detrimental effect of unregulated boating and diving activities should be taken into account. I understand that such a potential threat might not be considered as important or as priority interms of management as others (e.g global warming effects, sediment and nutrition runoffs, or overfishing). The Red Sea (case study), for instance, lacks freshwater runoffs, freshwater precipitation is minimal, and weather and sea conditions are optimal for coral reef growth. Coral bleaching has not been reported as a major threat in these region. What seems to be the problem there is unregulated diving tourism. In the Northern Red Sea (Egypt, Jordan, and Israel) diving tourism in considered as the major driving force for the economies of these resorts. I have seen areas on fringing reefs that were completely devastated by boat anchoring. These areas where once coral dominated reef sytems and now transformed to algal systems and coral rubble. Also, if these areas are visited by >100,000 divers a year, diver-induced physical damage could be high enough to suppress the system's ability to recover. Thereby, I think that some kind of emphasis should placed on the consequences of such a threat.