Human impacts on coral reefs in the Sultanate of Oman

A rapid assessment survey of the coral reefs of the Sultanate of Oman was c onducted by the Ministry of Regional Municipalities and Environment during the first half of 1996. The survey revealed new information on the distribu tion pattern of corals in Oman and identified impacts, threats and potentia l threats to coral communities for the purpose of preparation of a National Coral Reef Management Plan (Phase One of the implementation of a National Coastal Zone Management Plan). Impacts on coral reefs in Oman were found to be attributable to both natural and human causes, resulting in significant and widespread degradation. Damage resulting from fisheries activities was the most commonly recorded human impact, with the most severe effects. Oth er human impacts resulted from coastal construction, recreational activitie s, oil pollution and eutrophication. Predation of corals by Acanthaster pla nci, damage caused by storms, coral diseases and temperature-related stress were the most commonly recorded natural impacts to coral reefs. Further mi nor natural impacts were attributable to siltation, rock falls and predatio n by a corallivorous gastropod (Drupella sp.). Significant differences betw een different areas of the country were found in terms of human impacts on coral reefs and these were related to coastal demography and human activity . Eighty per cent of sites studied were recorded to have been affected by h uman impacts to some degree. Impacts attributable to fisheries activities w ere found at 69% of the sites. Lost or abandoned gill nets were found to af fect coral reefs at 49% of sites throughout Oman and accounted for 70% of a n severe human impacts. Lost gill nets were also found to have a negative a ffect on fisheries resources and other marine wildlife. Observations of the behaviour of gill nets on coral reefs suggested a predictable pattern of d amage over time and a significant increase in damage intensity during storm s. Fishing nets were found to act selectively, causing greater damage to ce rtain coral communities than to others. Results of the study are discussed in relation to management of coral reef areas in Oman. (C) 1999 Academic Pr ess.