Marine scientists in Australia undertaking the world’s first large-scale investigation of the impact of climate change on coral reefs suggest that many of them would survive the ravages of warming.
“Coral reefs are sometimes regarded as canaries in the global climate coal mine – but it is now very clear than not all reef species will be affected equally,” explains Terry Hughes, professor and director of the ARC Centre of Excellence for Coral Reef Studies at James Cook University, who led the study.
The emerging picture, he says, is one of ‘winners and losers’, with some corals succeeding at the expense of others. Rather than experiencing wholesale destruction, many coral reefs will survive climate change by changing the mix of coral species as the ocean warms and becomes more acidic, the journal Current Biology reports.
This, in turn, has implications for humans, who rely on the rich and beautiful coral reefs of today for food, tourism and other livelihoods. “A critical issue for the future status of reefs will be their ability to provide ecosystem services like reef tourism and fishing in the face of the changes in species composition,” said Hughes, according to an ARC statement.
“For example, if susceptible table and branching species are replaced by mound-shaped corals, it would leave fewer nooks and crannies where fish shelter and feed,” Hughes added.
The research team carried out detailed studies of the coral composition of reefs along the entire length of Australia’s Great Barrier Reef.
They identified and measured a total of 35,428 coral colonies on 33 reefs from north to south. Studying corals on both the crests and slopes of the reef, they found that as one species decreases in abundance, another tends to increase, and that species wax and wane largely independently of one another.