Largest coral re-planting project launched on the Great Barrier Reef

Scientists have launched the largest ever attempt to regenerate coral on the endangered Great Barrier Reef by harvesting millions of eggs and sperm during their annual spawning. The researchers yesterday announced plans to grow coral larvae from the harvested eggs and return them to areas of the reef that have been severely damaged by climate-related coral bleaching.
"This is the first time that the entire process of large-scale larval rearing and culture has been undertaken directly on the reefs of the Great Barrier Reef," said Peter Harrison of Southern Cross University. one of the project leaders. "Our team will restore hundreds of square meters in order to reach square kilometers in the future, a scale never tried before," he said in a statement.
The launch of the "Larval Restoration Project" was planned to coincide with annual coral reef deposition, which began earlier this week and will last only 48 to 72 hours. Corals along large swathes of the reef spread over 2,300 km were destroyed by rising sea temperatures related to climate change, leaving behind skeletal remains during a process called bleaching corals.
The northern parts of the reef have suffered two consecutive years of unprecedented severe whitening in 2016 and 2017, raising fears of irreparable damage. Harrison and his colleagues hope that their reseeding project will help reverse the trend, but warned that the effort alone would not save the reef. "Climate action is the only way to ensure the survival of coral reefs," he said.
"Our approach to reef restoration aims to give coral populations the time they need to survive and evolve until emissions are capped and the climate stabilizes."
Scientists hope that corals that have survived bleaching will have greater tolerance for rising temperatures, so that a reproductive population from this year's spawning will become a coral better able to survive future bleaching episodes. The researchers, who also include experts from James Cook University and the Sydney University of Technology (UTS), said one novelty of their reseeding project was to grow larvae coral with microscopic algae. Both live in symbiosis on the reef.
"So we are aiming to accelerate this process to see if the rapid absorption of algae can boost the survival and early growth of juvenile corals," said David Suggett of UTS.