Some corals could adapt to climate change by swapping algae that live inside their tissue for types that are more tolerant to warmer oceans, a new study published on Monday said.
The phenomenon of bleaching – when algae is expelled from overheated tissue – makes the coral more susceptible to disease and death.
The microscopic algae are the corals’ primary food source and give them their colour.
But researchers from the US found that coral could survive moderate climate change depending on the type of algae present, a report in the journal Nature Climate Change found.
Previous studies have shown that algae could return to bleached coral within weeks if conditions improved, which in turn could make coral more tolerant to environmental changes.
The study modelled the response of coral to four climate scenarios.
It found that tolerance levels could be affected by the type of algae present, which themselves could adapt to environmental changes.
The findings could be used to help conserve coral in the future, said the researchers,
Reefs are at increased risk as temperatures increase.
Severe coral bleaching affected the central third of the Great Barrier Reef, the world’s largest reef system, in 2016 and 2017 because of unusually warm sea temperatures off the coast of Queensland, Australia.