NSW Government scientists are undertaking research into a little understood disease that has the potential to impact on the states intensive aquaculture sector, Minister for Primary Industries Ian Macdonald announced today.

"Nodavirus has been acknowledged nationally as a major aquatic health issue and this government is responding to the need to address this important matter," Minister Macdonald said.

"Currently there is very little known about this infection, particularly the manner in which it impacts on Australian bass, especially in broodstock.

"This is an important issue for recreational fishers because Australian bass are produced specifically for stocking freshwater impoundments and rivers in order to create and enhance new recreational freshwater fisheries.

"The more scientists understand about the nodavirus infection the more able they will be to develop strategies to breed and release nodavirus free stock into the rivers and inland waterways of NSW for recreational fishers to enjoy.

Industry & Investment NSW (I&I NSW) virology scientist Dr Peter Kirkland said the three year project would entail the progressive study of a sample batch of known infected fish to determine if they can give information about the persistence of nodavirus infection.

"Prior to an outbreak in production batches of Australian bass fingerlings in 2004 nodavirus had never been detected in NSW," Dr Kirkland said.

"This particular project aims to determine the persistence of nodavirus in Australian bass that appear to have become infected in the late larval/early fingerling stage of development yet have maintained health.

"In determining the possible routes of infection and its persistence we are better able to better reduce the risk of spreading nodavirus in the wild.

"It is currently unknown if nodaviruses are prevalent in native fish populations in NSW."

Minister Macdonald said researchers from I&I NSW and Sydney University are working closely with commercial hatcheries.

The research project is funded by the NSW Freshwater Fishing Trust and supported by recreational fishing groups.

"Money raised from the sale of the recreational fishing licence fee is placed into two trusts, one for saltwater and the other for freshwater, which must be spent on projects to improve recreational fishing in NSW," Minister Macdonald said.

"The Recreational Fishing Trusts mean anglers can rest assured that the fees they pay for their licences are reinvested into worthwhile recreational fishing projects that directly benefit them."

The longitudinal study of nodavirus infection in Australia will be complemented by a multi jurisdiction Fisheries Research and Development Corporation (FRDC) project designed to address diagnostic issues and to suggest strategies for the control of the disease.

A second I&I NSW research project, the Evaluation of the status of nodavirus carrying Australian bass in NSW waterways, conducted by I&I NSW research scientist Dr Stewart Fielder will further boost the study by seeking to understand the status of nodavirus in wild populations of Australian bass in NSW.

"The evaluation study of wild populations, also funded by the NSW Freshwater Fishing Trust, seeks to discover whether nodavirus is endemic in wild bass populations," Dr Fielder said.

"The result of the study could impact on the current method of testing on hatchery produced fish and the development of appropriate policy for managing risks in freshwater fisheries."

Further reading

DAFF Nodaviruis biosecutiry page

Investigations of nodavirus infections in Australian bass

Media contact: Rebecca Bowman 0438 247571