Consultant food technologist Alan Speight called the state of aquaculture "a timebomb" and "a tabloid story waiting to happen".
He questioned fish farms' high dependence on antibiotics to control diseases, which would otherwise flourish where high fish stocks were kept in limited areas. "Fish farms are where poultry farms were 20 years ago in terms of veterinary medicine. The last figures I saw on the usage of antibiotics were very high."
While notionally supporting sustainable fish farms, Speight highlighted the risk to wild fish from disease-carrying fish escaping farms and poor international traceability.
A spokeswoman for Sustain, which campaigns for better food and farming, said feeding carnivorous farmed fish unsustainably sourced fish undermined the concept of sustainable aquaculture. "The Marine Stewardship Council (MSC) is trying to certify sources of fish feed and the Soil Association's organic food standards require it."
She said the fledgling Aquaculture Stewardship Council's (ASC's) certification of sustainable fish farms was a tool to encourage truly sustainable aquaculture, especially because it was backed by sustainability champion WWF.
The comments came as the Findus Group revealed its support for the ASC scheme. But, according to Mike Mitchell, technical director of the Seafood Company, Findus is unwilling to publicly commit to it until it is fully formed. Mitchell said consumers could already buy products containing ASC-certified fish. Current certification was bolted on to GlobalGap certification, but the ASC mark would take off next year, he said.
"It's then going to take time to gather impetus," said Mitchell. "As a major seafood buyer we could generate participation at farm level."
ASC would harmonise existing certification programmes for fish from sustainable aquaculture and provide a counterpart to the MSC certification scheme for sustainably sourced wild fish, said Mitchell. "There isn't unity in these schemes. That's why we're supporting the ASC label."
For its Fish For Life initiative, the Findus Group also aims to ensure all wild fish it buys for its Findus and Young's retail brands will be MSC-certified by 2012.
Separately, Simon Crutchley, chief executive of South African firm AVI, which has deep-water trawling and processing interests, has launched an impassioned plea to back sustainable wild fisheries.
At the 2010 Summit of the Global Consumer Goods Forum in London last month, Crutchley said fish meal and oil was a rich protein source for animals as well as humans. "30% of the world's fish stocks are ground into fish meal or oil," he said. As a result, sustainable wild fisheries were vital to overall food security.