Coral reefs are among the most important groups of ecosystems in the world because of their high diversity, high productivity and economical benefits to humans. Modern reef-coral genera have been in existence for more than 50 million years and, during this time, they have weathered many natural disturbances. Nevertheless, over the past fifty years these ecosystems have experienced an overwhelming succession of rapid disturbances most of which have been induced by humans, such as, overexploitation of resources, agricultural pollution and climate change. The following study collected data using the point transect method for coral and macroalgae cover and the Shannon Wiener Index (H) for species diversity at six sites along the Belizean Barrier Reef Complex. The data was analyzed to determine if there were significant differences between sites in relations to coral and macroalgae cover, coral diversity and if there was any sign of recovery from the effects of the mass bleaching and hurricane Mitch in 1998. Results show a recovery of coral cover and increased coral diversity between data from 1999 to 2010. In relation to macroalgae, there were no significant differences between years. The recovery can be attributed to a shift in species dominance from Montastrea annularis to Siderastrea siderea a species well known for being resistant to wave action and sedimentation. Coral diversity (H=2.24) was highest in 2010. This increase in diversity is attributed to an increase in evenness of species rather than to an increase in species richness. Based on the Simplified Integrated Reef Health Index (SIRHI) grading using coral cover and macroalgae cover for the Mesoamerican Barrier Reef System, all sites are in good condition and only Nicholas Caye stands in a poor condition.
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