Starfish have a general bad reputation for being a coral eater...
you're so right...I found the news about ...killing starfish !! Sad but true !!Scientists: To save Great Barrier Reef, kill starfish
[by: CNN's Brad Lendon]
Australia's Great Barrier Reef has lost 50% of its coral since the mid-1980s, much of that because of a ravenous species of starfish that can each consume some 12 square yards (10 square meters) of coral in a year, scientists reported Tuesday.
According to a study by the Australian government's Institute of Marine Sciences and the University of Wollongong, the coral cover on the world's largest coral reef ecosystem suffered damage from tropical cyclones (48%), the crown-of-thorns starfish (42%), and coral bleaching (10%).
If current trends continue, the reef will lose another 50% of its coral in the next 10 years, the scientists said.
Stopping the starfish infestation is the one thing humans can do that can save the reef, they said.
According to the study, the starfish in its larval stage feeds on plankton, populations of which surge when fertilizer runoff floods the coastal ocean waters with nutrients. So plentiful plankton can lead to swarms of hungry starfish.
The starfish consume the corals by climbing onto them, thrusting out their stomachs, and bathing the coral in digestive enzymes, which liquefy it for ingestion. Adult crown-of-thorns starfish, ranging in size from 9 to 18 inches in diameter and with up to 21 arms, can eat nearly a square foot of coral each in a day.
**** Besides protecting the environment, WWF said loss of the reef means loss of jobs for Australians.
“Sixty thousand jobs in the tourism industry depend on us acting with urgency over the next few years,” the WWF's Heath said in a statement.