Thermal tolerance is associated with enhanced growth and recovery in the reef-building coral Montipora capitata

Relationships between ecologically important traits are increasingly important for the future of coral reefs, which are declining globally due to a variety of stressors. Corals that resist and recover from bleaching will be selected under future climates, which may negatively or positively impact a range of associated traits that are important for the structure and function of contemporary and future reefs. We investigated growth under ambient conditions, bleaching tolerance, and recovery in a model population of 60 Montipora capitata colonies harboring diverse symbiont communities. Specifically, we determined percent change in surface area and buoyant weight over a 3 mo ambient period, degree heating weeks required to reach a 30% decline in photochemical efficiency ( F _v / F _m ) in a 2 wk heat stress assay (27-32°C), F _v / F _m rebound over 80 d, and baseline Durusdinium and Cladocopium spp. communities in all genotypes. We observed higher trait variance among Durusdinium -dominated corals, highlighting the interaction between host and symbiont. Durusdinium -dominated corals displayed higher thermal tolerance and stress-induced mortality than Cladocopium -dominated corals, but there was no association between symbiont community and coral thermal stress recovery or growth. Thermal tolerance was also positively correlated with recovery after equivalent stress, and corals with moderate to high tolerance exhibited the highest surface area change. These results demonstrate limited tradeoffs associated with thermal tolerance in M. capitata and suggest that thermally tolerant corals in this model system can effectively recover from stress and maintain moderate-to-high growth rates under ambient conditions, providing insight into the adaptive capacity of thermally tolerant corals in the Anthropocene.