Not all starfish get a gold star when it comes to reef health. Despite being native to the Great Barrier Reef, large outbreaks of the coral-crunching crown-of-thorns starfish pose a significant threat to its survival.
Australian Institute of Marine Science research shows that over the past 30 years, coral cover on their surveyed reefs declined by about 50 per cent. Crown-of-thorns starfish were responsible for almost half of this decline. In fact, without these predatory starfish devouring reef corals, researchers estimate that there would have actually been a net increase in average coral cover.
But it’s not all bad news – there is a slice of silver lining under that spiky crown.
The Great Barrier Reef Marine Park Authority says the coral-eating starfish plays an important role on healthy coral reefs. Because it tends to feed on the fastest growing corals such as staghorns and plate corals, this allows slower growing coral species to form colonies. This helps increase coral diversity on reef ecosystems.
Taking AIM at the crown-of-thorns starfish – with giant killer snails of course
A new federal government funded project at the Australian Institute of Marine Science (AIMS) is taking aim at the crown-of-thorns starfish with a breeding program of the starfish’s natural predator, the giant triton sea snail.
This project builds on the success of previous AIMS research which found that crown-of-thorns starfish will actively try to avoid an area where triton sea snails are present.
And when you see what happens when this spiky starfish meets its nemesis, it’s not hard to see why they’d want to steer clear!
Not even the starfish’s sharp spines complete with toxic coating can deter these giant snails from making a meal of them.
Find out more about the AIMS giant triton breeding program