Global Distribution of Hard Coral Pathogen Vibrio coralliilyticus; an Ensemble Modelling Approach

Declining reef-building corals around the world is a pressing issue. Infectious diseases are known to be a major cause of mass coral mortality. Vibrio coralliilyticus , a bacterial species, has gained increasing focus as an etiological agent of white syndrome in corals. The present study used nine types of model algorithms accomplished in the Species Distribution Modelling package, Biomod2, in the R statistical software to develop an ensemble global current prediction map of the coral pathogen, V. coralliilyticus . Based on the worldwide occurrence data, the pseudo-absences created using random strategy in the modelling package, and the data of nine environmental predictors, we generated a global ensemble model for predicting the susceptibility of hard corals to the pathogen. The ensemble model outperformed individual models with a True Skill Statistic (TSS) value of 0.987 and a Receiver Operating Curve (ROC) value of 0.998. Mean bathymetry is the most influencing environmental variable, followed by mean Sea Surface Temperature (SST). A high probability of the species was observed in the Hawaiian group of islands, the southern reefs of the Coral Triangle, and the Great Barrier Reef (GBR). The prediction results can aid in the epidemiological management of V. coralliilyticus infections in reef systems.