SYDNEY (AFP) – Mass coral spawning has begun on Australia's Great Barrier Reef, with early indications that the annual event could be the largest in recent years, said local marine biologist, Sunday (17/11).
Eroded by rising sea temperatures caused by climate change and coral bleaching, the world's largest coral reef system becomes a frenzy once a year with the mass release of eggs and sperm coral that are synchronized to increase fertilization opportunities.
Marine biologist Pablo Cogollos, from a tour operator based in Cairns, Sunlover Reef Cruises, said the first night of spawning 2019 was mainly "productive", in a positive sign for threatened ecosystems.
"There are three times the volume of eggs and sperm compared to last year, when soft corals appeared four nights after the full moon and were considered the best coral spawning in five years," he said.
Natural wonders, which are likened to underwater fireworks or snow storms, occur only once a year under certain conditions: after a full moon when the water temperature ranges from 27 to 28 degrees C.
Soft corals are the first to be released, followed by hard corals, in a process that usually takes between 48 and 72 hours.
Corals along a large plot of 2,300 km of coral have been killed by rising sea temperatures associated with climate change, leaving skeletal remains in a process known as coral bleaching.
The northern reach of the reef experienced two years of unprecedented bleaching in a row in 2016 and 2017, raising fears that it might have suffered irreparable damage.
Scientists last year launched a project to harvest coral eggs and sperm during spawning, from which they plan to grow coral larvae and use them to regenerate badly damaged reef areas.