IVF offers hope for dying coral
Corals grown using IVF have spawned for the first time on the threatened Great Barrier Reef, raising hopes of saving the world’s largest living structure from global warming.
Scientists say a coral breeding population has been established on the 2250-kilometre reef using transplanted specimens.
It involves collecting spawn – microscopic eggs and sperm – from healthy corals, and settling the larvae into tanks and nursery pools on the reef. After a couple of weeks, the coral polyps are attached to restore and repopulate damaged reefs.
During the Great Barrier Reef’s late November spawning event, trillions of eggs and sperm erupted into the ocean in plumes of red, yellow and orange to reproduce – a scene that happens only once a year. Among them were spawn from the reef’s first IVF ‘‘babies’’, now sexually mature corals, which were placed at Heron Island five years ago.
Researchers revisited 22 large colonies born through the first coral IVF trial, and found that they had survived a bleaching event and grown to maturity. In this year’s spawning event, they produced their first batch of coral larvae.
‘‘This is a thrilling result to see these colonies we settled during the first pilot study on Heron Island grow over five years and become reproductive,’’ said Professor Peter Harrison, of Southern Cross University in Queensland.
Meanwhile, scientists can tell whether an effort to save a tropical coral reef is going well because happy fish will sound as if they are blowing raspberries, a British study has found.
The research suggests that whoops, croaks, growls, raspberries and foghorn-like noises from fish can help to demonstrate that a reef that is being restored is in rude health.
The researchers studied thousands of square metres of coral being grown on previously destroyed reefs in Indonesia.
The study, led by scientists from the University of Exeter and the University of Bristol, recorded a diverse collection of sounds. They believe that these noises – many of which had never been recorded before – can be used alongside visual observations to monitor whether these habitats are healthy.