More research is required before a decision on whether to release the carp herpes into Australian waterways is made, a report has found.
The long-awaited National Carp Control Plan (NCCP) outlines how biological control methods could be used to reduce carp numbers.
The report does not explicitly endorse releasing a virus to control populations, but does outline the steps that would be required before doing so.
According to the report, a carp herpes virus could reduce and suppress populations by 40 to 60 per cent and by up to 80 per cent in less resilient populations.
It recommends further research into how the virus could affect other fish species, including native species, and undertaking more real-life modelling on Australian variants of carp.
The report found research has been limited to laboratory conditions under Australian biosecurity laws because the virus is exotic.
Concerns remain around impacts on water quality from decomposing fish, how long the virus would remain effective at killing carp and whether it could infect native fish populations.
An Agriculture Department spokesperson said it could take several years to complete the necessary research before the virus could be released.
"As an established pest species, the eradication of carp is unlikely," the spokesperson said.
"The purpose of the NCCP is to assess how effective the carp virus could be in controlling carp populations."
There will also be no immediate public consultation on the report.
"Extensive public consultation was undertaken during the development of the NCCP and this is outlined in the NCCP documentation," the spokesperson said.
"If agriculture ministers decide to proceed with the biological control program, further public consultation will certainly occur before any virus release."
Lingering concerns
Federal Agriculture Minister Murray Watt told the Victorian Country Hour he only received the document for the first time today and that it still needed to be reviewed by the National Biosecurity Committee.
"[The report] suggests there's research that shows using that virus would be an effective control measure for carp," he said.
"But of course we've got to think about the wider impacts of introducing that kind of virus.
"It seemed to me the recommendations were you could consider using it in a more targeted manner, rather than just going and plonking it into every river system right around the country."
The government says the plan, formulated over six years, is the largest feasibility assessment of a biological control agent in Australia.
It involved 11 national and international research institutions.
The Commonwealth allocated $15.2 million May 2016 to investigate the feasibility of the Cyprinid herpesvirus 3 as a biological control agent for common carp.
Of the original funding, $10.4m was allocated to the Fisheries Research and Development Corporation (FRDC) to undertake the feasibility assessment that became the plan.
Today's report also assesses the effects mass fish deaths could have on different parts of the Murray-Darling Basin system, including the cost of cleaning up as well as the social and tourism impacts.
Case studies undertaken as part of the plan estimate the total cost of implementing the plan in the Murray and Murrumbidgee river systems at about $190 million.
"It may be there's a bit more research needed into the plan before we go following it holus-bolus," Senator Watt said.
