CRED REA Coral Health and Disease Assessment at Swains Atoll, American Samoa in 2008

Coral health and disease assessments were conducted along 2 consecutively placed 25-m transects, as part of Rapid Ecological Assessments conducted at 8 sites at Swains Atoll in the American Samoa during 22 February - 19 March 2008, aboard the NOAA Hi'ialakai Reef Assessment and Monitoring Program (RAMP) Cruise HI0802. Within an area of 1-3m on each side of both transect lines, each colony was inspected and every diseased/afflicted coral enumerated and identified to the lowest taxonomic level. For each affected coral the following information was recorded: colony size, type of affliction, area affected, percent live/dead, and severity of the affliction (mild = 1-10%, moderate = 11-25%, marked = 26-50%, severe = 51-75%, acute = 76-100%). Coral afflictions were classified into one of six general categories (following Willis et al., 2004) including: bleaching, tissue loss, black band disease, skeletal growth anomaly, predation, and other lesions. This latter category included algal overgrowth, as well as unidentified syndromes causing deterioration of scleractinian corals. Tissue samples of selected cases were procured for histopathological analyses. These data provide the basis for computing quantitative estimates of disease incidence and prevalence. Samples and photographs provide aid in further disease characterization and description. Histological tissue samples are traditionally fixed in a formaldehyde solution prior to preparation for processing and analysis.