The significance of coral disease epizootiology for coral reef conservation

There are many aspects of coral disease that are poorly understood. The rel ationship, if any, between human activities and the incidence of coral dise ase is particularly important since it is frequently assumed that the numbe r and prevalence of diseases are increasing, and are indicative of a genera l decline in the marine environment. Certainly a good understanding of thes e issues would assist in the conservation of coral reefs by identifying tar gets for mitigating management programmes. In situ observations of coral di sease and associated mortality were therefore compiled from more than 150 s ources, and reviewed. Although there have been cases where disease has caus ed major changes in the composition and structure of reefs, most notably in the Caribbean, these are exceptions when compared to the number of locatio ns at which disease has been observed. With the exception of white-band dis ease, most frequently observed diseases do not appear to be specific in the ir host requirements, affecting species in many different genera. The overw helming majority of disease in the Caribbean (97% of locations) has been re corded from coral reefs where human activities are expected to have medium to high impacts. Regional scale patterns in the incidence of coral disease may therefore be suitable bio-indicators of disturbance to coral reefs. Thi s potential relationship should be investigated further with a view to usin g patterns of disease to monitor specific sources of stress on reefs. (C) 2 000 Elsevier Science Ltd. All rights reserved.