The Great Barrier Reef is once again at risk from an outbreak of the 'killer' starfish, the Crown of thorns.
Outbreaks of the live coral-eating Crown of thorns starfish (Acanthaster planci) have been a major issue for the barrier reef over the last 40 years with the last outbreak occurring in 2003. Usually the coral cover returns in between outbreaks but scientists are extremely concerned as coral cover is at its lowest level since records began in 1985. As a result Cairns tourism operators are calling on the Federal Government to support their efforts to stop the pest.
The starfish can grow up to 80kg in weight and can eat their size in coral cover every day. Hundreds of them have already been found in the stretch of reefs off Cairns and Port Douglas. Executive director of the Association of Marine Park Tourism Operators, Col McKenzie, said: "We're at the very start of another outbreak. We want to get early action - if we don't it will get worse."
Scientists are unsure as to the reason behind outbreaks; possible suggestions include a lack of natural predators due to overfishing or human influence on water quality. Australian Institute of Marine Science research director Dr Peter Doherty said conditions were ripe for another outbreak because major floods prompt increased spawning of Crown of thorns starfish. Past outbreaks have started near Cairns and spread to the southern tip of the Reef.
Although Cairns tourism operators and the State government have already invested a combined total of $4.2 million to fight the invasive species, they are drafting a letter to Federal Environment Minister Tony Burke to request a further $1.2 million for an intensive three-year eradication program.
The money will be used to train extra Crown of thorns control divers, who inject sodium bisulphate into the invasive pest to kill them.
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