IVF coral spawns for first time, paving way for Great Barrier Reef repair
Replanted corals at Queensland’s Heron Island grown from spawn collected in 2016 and planted on damaged corals have in spawned for the first time, proving a trial to repair damaged coral could work on the Great Barrier Reef.
The idea had been proven by Southern Cross University coral specialist Peter Harrison on reefs near Singapore since 2015.
But until late November’s coral spawning season, the idea had never been proven on the Great Barrier Reef.
The common but water chemistry-sensitive acropora coral species were chosen by Professor Harrison in 2016 when his team began the Coral IVF program.
The coral IVF trial sites at Heron Island off Gladstone were expanded in 2018 and 2019 to popular tourist spots at Moore Reef and Lizard Island off Cairns.
“On Singapore reefs we have been getting corals growing from ‘invisible’ millimetre site baby corals, up to dinner plate-sized corals in three years,” Professor Harrison said.
“And they have become sexually reproductive in three years.”
At Heron Island the same process has taken five years because of the cooler ocean temperatures in the southern Greater Barrier Reef.
“On the Great Barrier Reef, this is the first time – the first cycle – where anyone has been able to show the growth of corals right from larvae settling on the reef through to the reproductive aspects,” he said.
Professor Harrison said he always anticipated the coral would grow from the collected spawn slower in the southern Great Barrier Reef.
He believes it proves the scheme, involving collecting sperm and eggs from spawning coral and attaching the subsequently grown baby corals onto damaged reefs – will be able to repair damaged reefs on a larger scale.
“The good news is – just as predicted – this process works just as well on the Great Barrier Reef as it does in the other reef systems I have been working on,” he said.
“We have grown for the first time sexually reproductive adults and therefore – when they spawned last week – proves the success of this process.”
In north Queensland the baby corals planted at the northern Great Barrier Reef trial sites are yet to reach sexual maturity and spawn – sending eggs and sperm from warmer water temperature-tolerant corals into the reef waters to be collected; and again replanted on to patchy, damaged reefs.
In larval pools at Lizard Island, millions of coral larvae collected during recent coral spawning events are now growing as “a quarter of million” baby corals on “settlement tiles”, made from crushed ancient reefs into shallow meshed areas.
From these larval pools they too will be re-attached back to the damaged reefs.
The issue now is “scale”.
“What that Heron Island result shows is that process does work. What we have been doing is developing new equipment to scale it up,” Professor Harrison said.
Collecting coral spawn is now routine, the time and dates are known – linked to full moons in October and November.
“We’ve calculated that we would need to start developing tens or hundreds of million of these juvenile corals to start getting to very large scale,” Professor Harrison said.
“All of that is doable,” he said.
“We just need the funding to develop more of these larval pools, put them in multiple reef locations so that instead of operating as a research project in just one reef location during each of those spawning periods, the way to scale it up now is to get dozens of teams working in many different reef areas during each of these coral spawning periods.”
The Coral IVF program is one of many programs partly funded by the Great Barrier Reef Foundation, which in 2018 signed a six-year, $443 million partnership with the federal government to invest on the Great Barrier Reef.
The broad concept is to attract private sponsorship over the six years to expand the $443 million by $357 million to $800 million as part of their Reef Trust Partnership.
After three years an additional $157 million has been pledged to the Great Barrier Reef Foundation’s Reef Trust by September 2021, managing director Anna Marsden said.
“At the Partnership midway point, more than 200 projects are under way with over 400 partners with 65 per cent of the grant committed, and we are on track to deliver against the partnership’s objective of achieving significant, measurable improvement in the health of the Great Barrier Reef,” she said.
“There has been $157 million pledged towards the Partnership’s leveraging target, and this is made up of gifts from individuals, corporates, trusts and foundations and research and project delivery co-contributions.”
Federal Environment Minister Sussan Ley said she welcomed the results to date.
“The deployment of millions of larvae will help replenish the reefs around Lizard Island which have suffered multiple disturbances since 2014; crown-of-thorns starfish, severe cyclones, and three mass coral bleaching events,” she said.