Fatal attraction

The crown-of-thorns starfish is one of the Great Barrier Reef’s fiercest enemies. It feasts on coral, leaving it bleached white and vulnerable to destruction in heavy storms.

But a team of UQ researchers has led a breakthrough discovery that could protect coral and, at the same time, save one of the world’s Seven Natural Wonders.

Husband-and-wife team Professor Bernard Degnan and Associate Professor Sandie Degnan believe they, along with research colleagues, can use the powers of attraction to eradicate the destructive starfish.

The international research team has decoded the scent given off from the starfish so the prickly pests can be lured to their capture.

“For an already struggling Great Barrier Reef, and indeed any reef across the Indo-Pacific region, these starfish pose an enormous threat due to the ability of a single female to produce up to 120 million offspring in one spawning season,” Professor Degnan said.

“Millions of dollars have been spent over many years on a variety of ways to capture crown-of-thorns starfish, whether it be via diver collection, injections or robotics.

“Now we’ve found the genes the starfish use to communicate, we can begin fabricating environmentally safe baits that trick them into gathering in one place, making it easier to remove reproductively-primed animals.”

The Degnans worked alongside a team of UQ researchers, and long-standing colleagues at the Australian Institute of Marine Science (AIMS), the Okinawa Institute of Science and Technology (OIST) and the University of the Sunshine Coast (USC).

The painstaking process of sequencing the crown-of-thorns genome and its pheromones was completed 30 years after Professor Degnan moved from his hometown of New York to Brisbane to study as one of UQ’s first international exchange students.

A graduate in marine biology and molecular biology, Professor Degnan developed an early fascination with the biodiversity of the Great Barrier Reef, and while at UQ’s Heron Island Research Station he met his future wife.

“I guess there is a nice story there about the reef bringing us together and now we’re working hard to develop novel ways to understand and preserve it,” Professor Degnan said.

“But beyond us, there’s personal history with some of the other researchers like Mike Hall at AIMS, who is one of our oldest colleagues and who came up with the original genome concept.

“Nori Satoh at OIST could be considered the grandfather of marine genomics and has been a very supportive friend, as has Scott Cummins of USC, who was a former research fellow in my lab.

“What I like most is that we’re finding a solution to a problem, not merely documenting it.”

Beyond the role their genomics breakthrough brings to controlling the crown-of-thorns, the Degnans believe it could have other environmental and economical benefits.

They believe a similar approach could be used to combat invasions of sea snails and other marine pests throughout the world. For fishermen and coastal communities, that’s a win on several fronts.

“I expect for local economies there could be some positive cashflow from the fishermen who collect and remove the crown-of-thorns starfish,” Professor Degnan said.

“Furthermore, as the reef becomes healthier, the benefits to a raft of industries from tourism to fisheries quickly follow.”

To learn more about UQ's marine research, visit uq.edu.au/heron-island-research-station.