Hope grows for carp control
The days of the European carp, the fish often described as the rabbit pest of the waterways, could be numbered.
A senior manager from the National Carp Control Plan has told a meeting of Murray Valley irrigators that there is promising research that could lead to a new control program.
‘‘There is every right to have hope, because we have a national science-based process to ask: is there a solution,’’ National coordinator Matt Barwick said.
‘‘That’s what we are in the middle of right now. The research is showing promise that we will have an understanding of what the problem is and what might happen if we fix it.’’
The scientists are looking at the implications of how a virus could be used to control the carp, similar to the release of myxomatosis to control wild rabbits.
‘‘We need to let the research run out to give us an answer to the questions about how it would work, what would be the costs and what would be the benefit.
‘‘The decision (to use or not use a virus) has to be based on the science.’’
He said most of the research was close to completion and a final recommendation may be only months away. Mr Barwick said research had found that if the tonnage of carp in waterways could be reduced by 30 per cent, the population of native fish would double.
He showed a Cohuna meeting organised by the Speak Up Campaign photographs of waterways which had been rid of the pest, but also warned that even a virus may not completely kill all carp.
In response to questions, he agreed that simply delivering environmental flows down the river, although helpful to all fish, would not remove the carp.
He said the virus currently being studied by the scientists was already living in 33 countries, having been introduced accidentally in many of them.
Carp (Cyprinus carpio) have been in Australia for more than 100 years and are now established in all states and territories except the Northern Territory.
They pollute about one million square kilometres of Australian landscape.
Carp dominate freshwater fish communities in south-eastern Australia — in many areas they comprise more than 80 per cent of fish biomass, exceeding 350 kg per hectare in some parts of the Murray-Darling Basin.
Learning about pest . . . Irrigators listen to a presentation on the carp pest problem.
Carp insight . . . Matt Barwick explains research on carp at a Speak Up Campaign meeting at Cohuna.