THE Peter Faust Dam has been closed to all shore activities following the outbreak of the noxious weed Mimosa pigra.
The weed started to germinate late last year as the dam water level dropped. Seeds began to germinate that had been under water for 15 years.
The infestation is the only known location of Mimosa pigra in Queensland.
Biosecurity Queensland officer Shane Haack, who supervises the Mimosa pigra eradication project for Biosecurity Queensland, said the exposed seeds were sprouting.
"So far this year we have destroyed 149 seedlings and conducted constant surveillance to ensure all plants are destroyed before they can flower and seed," Mr Haack said.
He said in late December when the dam was at 60%, seedlings were visible and a drop in the water level would expose many more submerged seeds.
The current capacity of the dam is 58.8%.
Mimosa pigra is a destructive plant that forms dense, impenetrable thickets up to six metres high that can choke waterways and smother pastures and wetlands," Mr Haack said.
"If it spreads it could severely impact farmers, fishing enthusiasts and the tourism industry throughout the Whitsunday area," he said. Whitsunday Regional Council officer Bren Fuller urged dam users to ensure they did not spread the weed.
"The risk of spread is greatly increased if people come into contact with soil contaminated by Mimosa pigra seeds," Mr Fuller said.
"That's why recreational activities such as camping, fishing from the shoreline, horse riding, four-wheel driving and pig hunting are not permitted at Peter Faust Dam," he said.
"When young, Mimosa pigra has a single prickly stem and green feathery leaves that close up when touched.
"When mature it looks like a branched shrub with lots of rose-like thorns."
Mimosa pigra is a restricted invasive plant, which means everyone has a obligation to take all reasonable steps to minimise the risk of spreading the plant and must report all sightings within 24 hours.
To report sightings call Whitsunday Regional Council on 4945 0261.
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