Photo gallery on cryptic coral species around Moorea (Burgess et. al., The Bulletin of the ESA)

Hidden Differences in Bleaching Among Cryptic Coral Species

Scott C. Burgess1, Erika C. Johnston1, Alex S.J. Wyatt2, James J. Leichter3, Peter J. Edmunds4

1Department of Biological Science, Florida State University, Tallahassee, FL, USA. 2Department of Ocean Science and Hong Kong Branch of the Southern Marine Science and Engineering Guangdong Laboratory, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. 3Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA, USA. 4Department of Biology, California State University, Northridge, CA, USA.

Coral bleaching in 2019 affected ~72% of Pocillopora spp. corals, killing 11–42% of Moorea colonies (French Polynesia). It first appeared that larger colonies bleached and died more than smaller. Genetic identification and censusing of colonies before and after bleaching revealed size-dependent bleaching to be hidden differences among at least five cryptic species. The haplotype in which most colonies died has so far only been found at Moorea. The results provide evidence for how co-occurring cryptic species could have contributed to resilience in the past through response diversity. Climate change, however, is expected to erode the importance of such diversity..