Conservation of Symbiodinium spp. clade in the coral Pocillopora damicornis during the 2014 mass-bleaching event
Symbiotic single-celled dinoflagellates play critical roles in providing corals with both energy and tolerances to survive over a range of environmental conditions. Stressors can cause the breakdown of this symbiosis, resulting in mass bleaching events, and are projected to increase in frequency and spatial extent, threatening the long-term survival of coral reefs. Recent studies have identified symbiont shuffling in corals towards more thermo-tolerant clades as a functional tool for their surviving thermally-induced stress events. However, this was not observed within Pocillopora damicornis colonies tracked over a complete bleaching to recovery cycle during the 2014 mass coral bleaching event in Hawai‘i. Instead, previously acquired symbiont clades were maintained following bleaching recovery. This observation suggests additional factors may be involved in thermal-stress acclimation and adaptation in this coral.