THE endangered lungfish may have survived the axed Traveston Crossing dam but environmentalists say it's under renewed threat because of the floods.
The federal Environment Minister, Peter Garrett in November knocked back approval for the dam on the Mary River, near Gympie on environmental grounds. He said the dam would have "serious and irreversible effects" on nationally listed species such as the Australian lungfish, the Mary River turtle and the Mary River cod.
On Friday, the Queensland government-owned, SunWater released 127,000 megalitres - more than 63,000 Olympic-sized swimming pools -- over the Paradise Dam spillway on the Burnett River, near Bundaberg.
Roger Currie of the Wide Bay Burnett Conservation Council said the lungfish in the dam would probably be injured or killed going over the spillway.
"Even if they survive the spillway fall they won't be able to get back upstream to breed in their established breeding areas because they won't use the fish ladder," he said.
The fish ladder or "fishway" transfer system was designed to help the fish cross the dam wall as part of conditions imposed by the Federal Government before it approved the dam.
Mr Currie said only three baby lungfish had successfully used the Paradise Dam fishway since it was installed in March 2006 but no adult lung fish had used the device.
He said the group had asked SunWater about 10 days ago to release water slowly from irrigation channels at the bottom of the dam where the fish were unlikely to gather but this had not happened.
"I saw 13 endangered turtles bouncing down the steps of the spillway but no lung fish as yet," he said.
"There's potential for injury as fish pass over the stepped spillway and the bigger the fish, the greater the risk of injury," he said. Large fish such as adult lungfish, barramundi, striped mullet and Australian bass were known to migrate downstream during river flows and were at greatest risk of injury, he said.
Mr Currie said 30 lungfish had been tagged and some had transceivers to discover how many went over the wall and survived. A government report on their survival rate may not be available until June.
Last week was the first time the 300,000 megalitre dam had reached its capacity and Mr Currie said nobody knew how this would effect the endangered species.
The Primary Industries and Fisheries department spokeswoman said officers in a boat at the base of the dam were monitoring the spill and looking for fish on Friday until the situation became too dangerous. They would return next week when conditions were safer, she said.
SunWater did not respond to questions put to them.
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