New heat-tolerant algal species discovered in Abu Dhabi corals
Abu Dhabi: A new species of algae has been discovered in the coral reefs off United Arab Emirates’ (UAE) capital Abu Dhabi, an organism that helps corals survive seawater temperatures of up to 36 degrees Celsius, temperatures that would be lethal to corals elsewhere in the world.
In a collaborative project between New York University Abu Dhabi and Britain’s University of Southampton, researchers have identified a unique species of symbiotic algae that occurs in corals in the southern Arabian Gulf. The new species has been named symbiodinium thermophilum, after its heat-loving properties.
The breakthrough discovery was published this week in Nature’s journal, Scientific Reports.
“The Arabian Gulf is the world’s hottest sea,” said John Burt, associate professor of biology and head of the NYU Abu Dhabi marine biology laboratory.
“Abu Dhabi reefs can provide incredible insight into how corals may adapt to increasing temperatures expected under future climate change,” he added.
“We used novel molecular biological approaches to identify this species,” explained Jorg Wiedenmann, professor of biological oceanography and head of the coral reef laboratory at the University of Southampton.
“These approaches allowed us to get much higher resolution to distinguish these symbionts from those in other parts of the world’s oceans.”
Reefs are made up of many coral species, most of which live in a mutually beneficial relationship with microscopically small algae hosted in their tissue. These symbiont algae produce sugars that contribute to the diet of the coral in return for shelter and nutrients that are vital for algal growth.
However, the symbiotic association is vulnerable to changes in environmental conditions, in particular to increases in seawater temperature. Heat-stress induced loss of the algal partners from the coral host can result in the often fatal process known as “coral bleaching.”
“Understanding how corals survive under the extreme temperatures in the Arabian Gulf will give us important insights into the ability of reef corals to handle the heat stress, which is threatening their survival in the oceans that are warming up in response to climate change,” explained Wiedenmann.
“It gives hope to find that corals have more ways to adjust to stressful environmental conditions than we had previously thought,” he said.
“We monitored the stability of the symbiotic partnership seasonally for two years to ensure that this partnership was stable through a range of temperatures,” Burt said, confirming that this new type of alga is indeed a consistently dominant symbiont across several common coral species in Abu Dhabi.”
“This finding shows us the unique nature of corals in Abu Dhabi”, he said.
“But it also highlights the importance of coral reef ecosystems in the emirates and the need to ensure their conservation into the future.”
Recent conservation and research efforts supported by the Environment Agency-Abu Dhabi (EAD) have helped in this regard, Burt said.