Coral Reef Diseases in the Wider Caribbean

Abstract

Over the past few decades, coral reef communities around the world have been experiencing increasingly stressful conditions due to a combination of natural and detrimental anthropogenic factors. In the Caribbean, coral reefs have experienced significant losses in hard coral cover due in part to local habitat degradation, over-fishing, pollutant input, bleaching, hurricanes and more recently, diseases (Porter and Meier 1992, Ginsburg 1993; Aronson and Precht 1997; Epstein et al. 1998; Harvell et al. 1999; Wilkinson 2000; Weil 2001). These factors, acting alone or in synergy, can be highly variable on spatial and temporal scales, making it difficult to identify and characterize a single or combined cause(s) of reef deterioration. Bleaching events, for example, have increased in frequency and intensity in the last two decades and their impact has been highly variable both spatially and temporarily. In the Caribbean, bleaching has caused variable, but generally low, coral mortality, unlike the mass mortalities of the scale observed in the Indo-Pacific. In contrast, few coral diseases, with low prevalence and restricted geographic distributions, have been reported for the Indo-Pacific as compared to the Caribbean. The latter has been dubbed a “disease hot spot” because of the fast emergence, high prevalence and virulence of coral reef diseases and syndromes; their widespread geographic distribution, and the frequent epizootic events with significant coral mortalities (Epstein et al. 1998; Hayes and Goreau 1998; Green and Bruckner 2000; Weil et al. 2002). In the last few decades, for example, epizootic events have resulted in significant losses in coral cover, biodiversity and habitat (loss of spatial heterogeneity), and today, diseases have possibly become the most important factor in the deterioration dynamics of Caribbean coral reefs (Hughes 1994; Aronson and Precht 200 lb; Bruckner 2002; Weil 2002).