Coral metabolomic diversity is associated with restoration success.

As coral cover declines worldwide, coral propagation has become a necessary strategy to restore coral reefs. However, predation can negatively affect the survival of coral microfragments used in restoration. While predation in terrestrial plants is reduced via secondary metabolites that deter predators, the effects of secondary metabolites on coral survival and predation in the field are poorly understood. We placed Orbicella faveolata microfragments from ten different colonies in a predator-exclusion cage for 0 to 3 mo. We used untargeted metabolomics methods based on mass spectrometry to analyze metabolic patterns across lengths of time in the predator-exclusion cage. Betaine, a compound previously associated with temperature and predation stress, was found in higher abundance in fragments that experienced lower field survival and higher incidents of predation, suggesting a potential relationship with corallivory. Our results suggest a connection between the metabolome, fish predation, and survival of O. faveolata microfragments, and highlights a promising avenue to use secondary metabolites to enhance survivorship of coral fragments during restoration projects.