Small sea snail damaging world's coral reefs

Victoria University research has found that a small sea snail may be causing significant damage to coral reefs in the Pacific, even more so than climate change or coral bleaching.

Dr Jeff Shima, a Senior Lecturer in Marine Ecology and Director of Victoria’s Coastal Ecology Laboratory, has studied the worm snail Dendropoma maximum in the field at Moorea, French Polynesia.

"Our research looks at the effects of this often overlooked ‘zoological oddity’. It’s incredible that such a small snail can have such a significant impact.

"The adverse effects of this largely unstudied snail on coral reefs rival and exceed those of coral bleaching, climate change and human impacts. This small snail may be having a catastrophic impact."

The worm snails reduced skeletal growth of certain corals by up to 81 per cent and halved their survival rate. Susceptibility to damage varied among coral species.

Similar patterns of devastation have been recorded in other areas, such as the Red Sea. The snail is common in the Pacific and seems to be becoming more widespread.

Dr Shima says the loss of coral is significant because the reefs provide food and shelter for an incredible diversity of sea life.

"Coral reefs also support the economies of many Pacific island nations through fishing and tourism as well as being essential to the island’s own stability, protecting against storms, tsunamis and rising sea levels.

"This is a significant issue for us and our Pacific neighbours, many of which rely on aid from New Zealand yet only a small fraction of reef species, such as this snail, have been studied," says Dr Shima.

The research has recently been published in the prestigious international journal Biology Letters by the Royal Society, the national academy of science of the UK and the Commonwealth which celebrates its 350th anniversary this year.