World-first selective breeding of Ningaloo corals to fight impacts of climate change

The Minderoo Foundation program on the World Heritage-listed Ningaloo coast is a pre-emptive response to the mass bleaching which has already impacted the Great Barrier Reef.

Principal Researcher at Minderoo Exmouth Research Laboratory, Dr Kate Quigley, led the research team of 10 Australian and international scientists at Ningaloo for the annual mass spawning event.

Dr Quigley, a molecular ecologist who has previously bred coral than can survive 26-times better under elevated temperatures, hopes to cross-breed Ningaloo corals that will have a higher chance of survival in warmer temperatures.

“This technique is known as assisted gene flow,” Dr Quigley said. “It’s basically selective breeding, choosing the mums and dads of the same coral species during the mass spawning event that happens on Ningaloo and we’re able to identify the tough mums and tough dads to try to get tough babies that can survive better under warming conditions.”

The researchers chose corals from different sites along the Ningaloo coast based on the water temperature.

“We try to find sites that are really warm and highly variable and that’s where we find our heat tolerant corals and then we also go to coral sites that have lower temperatures, that have potentially less resilient corals,” Dr Quigley said.

“We collected corals that are ready to release their egg sperm bundles and bring them back to the Minderoo Exmouth Research Lab, a bespoke facility with a full team, where we are able to replicate the natural conditions and keep them comfortable so they will breed.

“After the spawning we’ve had baby corals, or larvae, in high-tech tanks and put them through a series of temperature experiments to see, of these individuals we’ve bred, who are the elite athletes – who are the ones that can really perform under high temperature and then we can use genetic techniques over the coming months to query what genes are responsible for these elite athletes,” Dr Quigley explained.

Dr Marie Strader, who heads up the Marine Molecular Ecology Strader lab at Texas A&M University in the United States, is collaborating with Dr Quigley in Exmouth looking at the genetic components of thermal tolerance in larvae and adult Ningaloo reef corals.

“We can actually look at the genome and look at how genes are turned on and off and particular patterns to give us clues about how these larvae are actually thermal tolerant at the molecular level,” Dr Strader said.

Masters student Alex Lago from Germany’s University of Bremen is also working with Dr Quigley on this world-leading research.

“The Ningaloo reef is the largest fringing reef system in the world and it harbours really high biodiversity and just as a unique ecosystem, we want to try and understand as much as we can so we can preserve that for future generations,” Ms Lago said.

Over the next year the researchers hope to understand if the assisted gene flow conservation technique could help to future-proof Ningaloo reef against mass bleaching events which are predicted to increase in frequency.