The South East Trawl Industry Association recently engaged CSIRO to conduct an optical acoustic survey of Orange Roughy numbers in waters off eastern Tasmania.
There is still considerable uncertainty about the exact size of the fish stock, with estimates ranging from 15,000 to 48,000 tonnes. However the research results indicate recovery is occurring with the population increasing significantly each year.
Due to the historical level of depletion and biology of Orange Roughy, the rebuilding of these stocks is likely to take some years yet.
Extensive fishing saw catches peak in 1990. Orange Roughy catch limits were introduced around the same time and reduced each year as more scientific information about the fish population became available.
In 2006 Orange Roughy was listed as conservation dependent and AFMA implemented the Orange Roughy Conservation Program to rebuild stocks to sustainable levels.
Under the program Orange Roughy is managed using a number of separate zones. Targeting Orange Roughy is prohibited in most zones with only very low levels of incidental and unavoidable catch allowed. In the Cascade Plateau zone (south west of Tasmania) fishing for Orange Roughy has been allowed for some years as the stock has been maintained at a healthy 60 + per cent of the original stock.
In the Commonwealth trawl sector, which targets popular table fish like Blue Grenadier, Tiger Flathead and Pink Ling, trawling below 700m is currently is prohibited to enable Orange Roughy to rebuild.
