Research helps identify corals most sensitive to climate change
Corals that survive bleaching produce offspring that are better suited to deal with the threat, according to research conducted in Bermuda.
The multiyear study began at the Bermuda Institute of Ocean Sciences (BIOS) in 2017, but the results were only recently published in the journal Global Climate Change.
Kevin Wong, a doctoral student at the University of Rhode Island and first author on the research manuscript, said: “We know parental history influences the characteristics of offspring in corals.
“The experimental design used in this study provides us with a unique perspective on how multiple types of thermal events can accumulate over time and have lasting consequences across generations.”
As part of the study, researchers collected mustard hill corals from two different reefs northwest of the island – crescent reef and hog reef.
After baseline information about the coral was collected, they were put into controlled environments for 21 days during their reproductive period.
While half the corals were placed into ambient temperature water (84F), the other half were placed in water that was slightly heated (88F).
After 21 days, the corals were studied for their physical health, including their respiration and photosynthetic rates, and monitored for the release of the coral’s larva.
The corals were then divided again, with half returned to their previous environment and half into the other.
They were then assessed a second time, with the results compared to the first.
The results showed that the corals that had been exposed to thermal stress produced offspring that were more capable of surviving in the environment, which suggests parent corals may be able to “precondition” their offspring to survive in new environments in the following year.
Hollie Putnam, ecophysiologist at the University of Rhode Island and researcher on the project, said: “The coral used in this study is a notoriously resilient coral and these findings potentially demonstrate how this species is so persistent across the Caribbean.
“Not all coral species are this robust to environmental stressors.
“However, this system allows us to unravel the mechanisms leading to resilience and identify which corals are most sensitive to climate change.”