Humans could save the Great Barrier Reef from global warming by transplanting corals that survive heat stress, say scientists.

A new joint study by the Australian institute of marine science (AIMS) in Townsville and the University of Texas has found a genetic basis for tolerance of higher temperatures in coral.

The discovery could pave the way for manmade colonies of coral bred to adapt to hotter oceans, according to the researchers.

University of Texas biologist Mikhail Matz said: “Averting coral extinction begin with something as simple as exchange of coral immigrants across latitudes, which … can be jump-started by humans moving adult corals”.

“This is occasion for hope and optimism about coral reefs and the marine life that thrive there,” Matz said.

AIMS evolutionary ecologist Line Bay said the discovery was a boon to “understanding of the potential for coral on the Great Barrier Reef to cope with hotter oceans”.

Researchers crossed individuals of branching coral Acropora millepora, from the warmer far north of the Great Barrier Reef, with members of the same species at Orpheus Island, 540 km south.



The corals of the north passed on their heat tolerance to their offspring, they found.

The study found heat tolerance could hinge largely on “mum’s genes”, being centred in mitochondria, the “powerhouses of the cells that are inherited solely from mothers”.

The scientists now wish to confirm the role of mitochondria in heat tolerance, suggested for the first time by the study.

That was the next step in identifying the “winners and losers in the game of climate change”, they said.

Only then could they consider attempts to restore reefs or make new ones by choosing heat-tolerant corals, or help those communities naturally took over from others that died.