A New Scientist article, referring to a new Nature report, describes how coral reefs are in some cases successfully adapting to higher water temperatures. The research, based on two studies, one led by Wildlife Conservation Society researcher Andrew Baker and the other by University of Guam researcher Rob Rowan, demonstrated that corals surviving a bleaching episode, or regrowing after bleaching, used a more heat-tolerant group of algae.
Coral reefs are composed of symbiotes, two species living together. The algae provide nutrients through photosynthesis, and the reef-building corals provide shelter and a location with access to light. Higher water temperatures can disable and kill the algae, leading to the eventual death of the reef. Global warming had been thought to threaten all the world’s coral reefs with destruction over the next few decades. Baker’s study, however, found that after bleaching events, the Symbiodinium C algae that are not heat-tolerant tend to be replaced with Symbiodinium D algae, which are more tolerant, and the corals regain health. So the corals will very likely survive. But will they be the same?
If you’ve seen the beach at little Hanauma Bay it is interesting to see that this coral is surviving.