Adult fragments of a coral species can better tolerate bleaching and recover faster when treated with tougher heat-evolved symbionts, new research from the Australian Institute of Marine Science (AIMS) and the University of Melbourne indicates.
The study also found that treatment with the heat-evolved symbionts did not compromise the coral’s ability to grow. This differs from previous studies on Great Barrier Reef corals which found that naturally heat tolerant symbionts could enhance heat resistance in adult corals, but at a cost to its growth.
Symbionts are the tiny cells of algae that live inside the coral tissue, providing corals with energy to grow. The survival of reef-building corals depends on this mutually beneficial relationship.
The symbionts used in this study had their heat tolerance bolstered in the lab by exposing multiple generations to elevated temperatures for 10 years. Adult coral fragments of a single species, Galaxea fascicularsis, that had been chemically bleached were then offered the heat-evolved symbionts. The scientists found the symbionts were able to maintain a symbiosis with adult corals for two years, promoting faster coral recovery from bleaching and enhancing their heat tolerance without trading off on growth.
Read more at Australian Institute of Marine Science
Image: DR WING YAN CHAN. (PHOTO: CHRISTIAN MILLER)