Spatial Ecological Patterns in Health-compromised Porites Corals

Coral diseases have become a major vector of change in coral reef physical architecture, functional ecology, and community structure. While the field of spatial community characteristics and coral disease research is growing, major gaps exist in the combination of the two areas of study. Here, I visually assessed over 100,000 massive Porites corals across 41 reefs in South Kona, Hawaii to investigate the spatial ecology of visually compromised corals. These corals were assessed for seven specific health conditions common to the region: algal infection, pigmentation response, algal overgrowth, Ramicrusta infection, skeletal growth anomalies, Porites trematodiasis, and tissue loss syndrome. Only 6.6% of corals surveyed exhibited a compromised health state and overall condition severity was low; less than 10%. Attributes representing colony assemblage structure showed few observed patterns with the severity and prevalence of these coral health conditions. Additional findings revealed that coral colony traits such as perimeter length had a positive effect on the presence of seven different coral health conditions. Whereas the interaction of both increasing colony surface area and perimeter length was negatively associated the presence of the health conditions. By using global and local spatial statistics, I uncovered trends in reefscape- and colony-level spatial patterns of health-compromised corals. Significant spatial structure existed among colonies based on their health condition severity. However, I found infrequent non-random spatial patterns in most reefs in South Kona.