Assessing coral health in South Water Caye Marine Reserve, Belize.

Coral form the basis of the most productive marine ecosystems on earth, but their health is threatened by numerous local and global factors. The repeated assessment of coral health can serve as a baseline against which to detect ecosystem changes and from which to craft appropriate interventions. In January 2022, the health of coral at five sites within and around the South Water Caye Marine Reserve, Belize was assessed using six aspects of coral ecosystem health: percent hard coral coverage; hard coral species richness and diversity; percent macroalgae coverage; the average color or bleaching-level of hard coral measured using CoralWatch color-matching cards, and the difference between the darkest and lightest colors on each coral. Across all sites, hard coral species richness ranged from 4 to 12 different species, while species diversity ranged from 0.42 to 1.63. Median percent coral coverage, average hard coral species diversity, and median percent macroalgae coverage were generally highest (~10% coverage) at two well-studied sites, Tobacco Caye and Carrie Bow; intermediate (~5%) at two other sites, Bread & Butter and Garden Patch; and lowest (,5%) at a previously unmonitored site, Emily's Split. All sites exhibited coral that were generally healthy based on median coloration scores of 3, and no site exhibited significant evidence of stress, based on a median difference in color scores greater than 2. Based on estimated percent hard coral coverage, these results suggest that, as of January 2022, the coral reefs at these five sites range from "Critical" to "Fair" status. [ABSTRACT FROM AUTHOR]