Assisted sexual coral recruits show high thermal tolerance to the 2023 Caribbean mass bleaching event

• DOI: 10.1371/journal.pone.0309719
• Publication Date: 2024-09-18T17:21:51Z
• Authors: Margaret W. Miller; Sandra Mendoza Qu...; Liam Lachs; Anastazia T. Bana...; Valérie F. Chambe...; James R. Guest; Alexandra N. Gutting; Kelly R. W. Latij...; Rita I. Sellares-...; Francesca Virdis; Maria F. Villalpando; Dirk Petersen
• Keywords: Thermotolerance; 570; Hot Temperature; Caribbean Region; Coral Bleaching; Coral Reefs; Reproduction; Animals; Anthozoa; Research Article

Assisted sexual coral propagation, resulting in greater genet diversity via genetic recombination, has been hypothesized to lead more adaptable and, hence, resilient restored populations compared common clonal techniques. Coral restoration efforts have resulted substantial of 'Assisted Recruits' (i.e., juvenile corals derived from assisted reproduction; AR) multiple species outplanted reefs or held situ nurseries across many locations the Caribbean. These AR provided context evaluate their relative resilience co-occurring during 2023 marine heat wave unprecedented duration and intensity that affected entire Populations six AR, most ranging age 1-4 years, were surveyed five regions mass bleaching season (Aug-Dec), alongside groups compare prevalence related mortality. Comparison included conspecific adult colonies as available, but also extant assemblages which conspecifics rare lacking, well small, propagated fragments. recruits had significantly lower impacts (overall pooled ~ 10%) than typically comprised larger (~ 60-100% depending on species). In addition, small fragmentation (rather propagation) two showed susceptibility intermediate between wild adults. Overall, exhibited high resistance under stress exposure up exceeding Degree Heating Weeks 20°C-weeks. As throughout globe are subject increasingly frequent intense heatwaves, activities include reproduction seeding can make an important contribution sustain populations.