'Won't die wondering': NSW to deploy aerators to keep fish stocks live
The state of many of NSW's rivers is so dire that the Berejiklian government will start installing aerators to increase oxygen levels and keep vital stocks of native fish alive.
Primary Industries Minister Niall Blair said on Tuesday that nine of these machines will be installed "as a temporary measure" to help fish populations survive the brutal combination of low river flows, algal blooms and severe heatwaves.
"We're not going to die wondering - we're trying to find a solution," Mr Blair told the Herald.
Each solar-powered aerator should be able to boost oxygen levels over an area about the size of a basketball court. "It's not a silver bullet," but it could keep some pockets of fish alive, he said.
Mr Blair was visiting the Keepit Dam in northern NSW, which is all but empty. Two of the aerators, trucked across the country from Western Australia, will be installed in remaining pools at that reservoir.
Four others will be installed on the Darling River, including near Menindee, site of the last week's massive die-off that killed as many as a million fish. These included endangered silver perch, as well as golden perch and giant Murray cod, some of which were decades old.
The other three machines will go to Burrendong Dam on the Macquarie River, where the Macquarie perch are also at risk, Mr Blair said.
Minister Blair said his department would look at adding enclosures to prevent poaching by anglers drawn to the remaining healthy fish stocks.
'All news to us'
Mr Blair repeated his concern that Tuesday's meeting of water officials in Canberra would fail to produce any clear outcomes.
Ministers weren't invited to the event, to be held at the Murray Darling Basin Authority from 2pm, and even federal Water Minister David Littleproud - who is in Berlin, Germany - won't attend.
"It was all news to us," Mr Blair said. "I'm at a bit of a loss - what is it going to do?"
Areas of immediate worry for more fish kills include the Murrumbidgee River and even the Murray River, although the extent of the problems mean "we're concerned pretty much everywhere", he said.
The Menindee fish kill was triggered by a sudden drop of temperatures after a severe heatwave nudged the mercury to 46 degrees. Dying blue-green algae resulted in further drops of already low dissolved oxygen levels, pushing many thousands of fish beyond their tolerance levels.
Much of inland Australia is forecast to exceed 45 degrees on Tuesday. For places such as Hay on the Murrumbidgee, the coming four days are predicted to hit 47, 47, 46 and 46 before cooling off to a maximum of 31 degrees by Saturday, according to the Bureau of Meteorology.
Menindee is also expecting similarly hot temperatures during this period.
'Band aid'
Richard Kingsford, director of Centre for Ecosystem Science at University of NSW, said that aerators are routinely used on dams supplying water to communities.
"It's a band aid," Professor Kingsford said. "They'll do a little bit for a little while. It still leaves a lot of river that's been affected."
Tim Beshara, federal policy director for the Wilderness Society, said that all governments needed to be looking at everything possible to help creatures survive the next few weeks and give the ecosystems to best chance to recover when it does rain.
"That might mean aerators, it might mean capturing populations of endangered fish and bringing them temporarily into captivity," he said. "This is the scary new world we now live in where we humans must play god to keep nature going."