Restoration stocks of a caribbean coral species contain low levels of inherent stony coral tissue loss disease resistance.

As coral diseases continue to devastate reefs worldwide, variation in disease resistance must be considered in conservation and management strategies. Stony coral tissue loss disease (SCTLD) has decimated Florida's Coral Reef since 2014 and is now endemic within the region. It has affected many endangered coral species, including the major reef-building species Orbicella faveolata; however, SCTLD resistance has been documented within this species. Utilizing O. faveolata in propagation for restoration efforts, we exposed 154 multi-locus genotypes to SCTLD during four sequential ex situ experiments. Four resistance groups were identified using measured disease phenotype metrics, but only 12 genotypes with multiple replicates were consistently resistant to SCTLD. Additionally, several genotypes were both resistant to SCTLD in the ex situ experiments and had a lower risk of SCTLD when outplanted in a targeted study in the Lower Florida Keys, indicating congruency in disease resistance in field and lab settings. However, long-term outplant survival was more variable, likely due to the interaction of multiple stressors and confounding variables. Although we determined overall low levels of inherent SCTLD resistance, our results support integration of resistance testing to multiple stressors, including disease, within restoration strategies to enhance outplant survival and recovery of reefs.