Scientists discover how coral-eating starfish communicate

Tokyo: Japanese and Australian scientists have discovered the communication patterns of a species of starfish that feeds on coral.

This discovery, the scientists hope, will help in the preservation of the coral reefs as a single specimen of the crown-of-thorns starfish consumes up to 10 sq. metres of coral meat per year and is responsible for between 37 per cent to 99 per cent of the decrease in live coral cover.

This crown-of-thorns starfish (Acanthaster planci) species is "one of the few animals that can eat corals", Ken Baughman, one of the authors of the study by the Okinawa Institute of Science and Technology, said on Monday.

The presence of this species, referred to by the locals as "onihitode" or "demon starfish", in the waters off the coast of the Japanese village of Onna in the Okinawa island was first reported in 1957.

A native of the Indo-Pacific region, this species is experiencing a boom in population that has resulted in tens of thousands to millions of starfish in population densities of 150,000 per sq.km.

"Normally, reefs only have a few," says Baughman, adding "But in recent decades the population outbreaks have tripled."

Baughman's team and Australian researchers analysed the starfish's genome, which for the first time has been completely sequenced.

It is "kind of like an instruction manual for how to build a starfish. We can better understand crown-of-thorns starfish biology" and consequently its behaviour, Baughman explained.