The Cayman Islands may represent a hope spot when it comes to coral survival.
Gretchen Goodbody-Gringley, a scientist with the Bermuda Institute of Ocean Sciences who visited the Central Caribbean Marine Institute in Little Cayman for several days recently, said the islands’ reefs have fared better than some other places in the Caribbean and around the world when it comes to coral health. Studying conditions here and the resilience of local species may provide clues for managing coral in other ocean environments, she said.
The researcher was here to discuss possible collaboration on a project with CCMI.
In a lecture last week at the National Gallery of the Cayman Islands, Goodbody-Gringley discussed her research on deep water corals and studying how corals manage the stress of changes in water temperature.
That research has focused primarily on deep water corals, specifically great star coral, which live at a depth of about 60 metres, or 200 feet. Visiting such depths requires highly specialised equipment and expertise.
Corals in that environment, Goodbody-Gringley said, experience less fluctuation in temperature than corals in shallow waters and are less susceptible to the types of bleaching events that have been seen in recent years. Although, some shallow water corals also seem to be less affected by such events.
“There are places that are doing OK,” Goodbody-Gringley said. “We’re calling them hope spots, places like Bonaire and Curacao and Bermuda, where the coral cover has maintained. It seems like Cayman might be another place.”
Goodbody-Gringley’s research involves determining how adaptive both these deep corals and those in shallower waters might be.
So far, she’s encouraged by the data.
“It suggests there is the scope for adaptation,” she said. “It’s a positive finding for the trajectory of coral survival.”
In the laboratory, Goodbody-Gringley said she has been able to show that the larvae of stressed adult corals develop a resistance to those stressors.
She’s also looking at the way water temperature affects algae. Healthy corals have a symbiotic relationship with certain algaes, particularly Zooxanthellae. Each organism benefits from the nutrients produced by the other. The relationship goes back millions of years.
When water temperature warms, however, the Zooxanthellae begins to produce toxins that are damaging to the coral. The coral rejects the algae, which results in bleaching. The algae is what gives coral its colour.
Finding algae species that are resistant to temperature change might also be a key in protecting corals, Goodbody-Gringley said. Some researchers are currently attempting to develop super corals, she said, where both the coral and algae are more thermoresistant.
That is important, she said, since another significant bleaching event is predicted for this year.