A team of researchers from the University of Sydney has made a surprising discovery about the role of crown-of-thorns starfish in coral reef ecosystems. Contrary to their reputation as reef destroyers, these predators may actually play a beneficial role in maintaining the balance of coral reef ecosystems. The study, published in Ecology and Evolution, found that when crown-of-thorns starfish populations are kept under control, they can help maintain healthy coral communities and support greater biodiversity. The researchers observed that nearly 75% of feeding events left behind living coral tissue, rather than destroying entire colonies. The team discovered that the starfish tend to consume fast-growing, dominant coral species, creating opportunities for slower-growing species to survive and establish themselves. This finding challenges the idea that all coral consumption by crown-of-thorns starfish is harmful. In fact, their feeding behavior may actually prevent a few dominant coral species from taking over the reef. The researchers caution that large outbreaks of crown-of-thorns starfish remain a serious threat, but the key difference is whether their populations remain at naturally manageable levels or grow into destructive outbreaks. The study suggests that removing every starfish may not be the best approach once an outbreak has been brought under control, and that culling should be complemented by strong marine management to protect COTS predators and keep COTS populations in check. The findings are consistent with the intermediate disturbance hypothesis, an important framework in ecology and conservation, which suggests that ecosystems can benefit from occasional, moderate disturbances that prevent any single species from becoming too dominant. The research has implications for conservation managers and scientists, who can use this knowledge to improve strategies for controlling crown-of-thorns starfish and maintaining the health of coral reef ecosystems.