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After 70 years of dramatic booms and equally spectacular busts, Tasmania’s scallop fishery entered the 21st Century looking just about dead in the water. Catches were zero, seabed surveys blank, fisheries shut, boats tied up and fishers and their families facing hard times.  Scallop fishing seemed doomed to become an occasional luxury.

By 2007 - just a few years later - catches are regular, prices firm and the remaining scallop fishers enjoying a new and unprecedented stability.

The miracle, says Malcolm Haddon, is down to an industry which took control of its own destiny and decided to fish for sustainability based on clear knowledge of its resource. The University of Tasmania fisheries scientist worked with the scallop fishers of Tasmania and Victoria through their darkest hours, and there is a touch of emotion in his voice as he recalls the transformation from goldrush mentality to guardians of the future.

“Back to the 1920s, the story of scallops was one of serial depletion. Every time new scallop beds were discovered there was a boom: boat capacity grew too fast and in no time the resource was fished out.  There were huge booms in each of the 1960s, 70s, 80s and 90s – and, with gear getting better all the time, they were fished out equally fast. Almost as soon as a new bed was found it was gone.”

The booms left a sour taste in the public mind. Scallops rotted in thousands because the market was glutted. An image implanted itself of “huge dredges with steel teeth, tearing up the seabed” that equated scallop dredging with clear fell forestry – unfairly given the huge difference in seabed ecology, Haddon believes.

In 2000, industry and scientists working together could find only one commercial bed of scallops left on the whole east coast. The Commonwealth fisheries closed in the previous year and the Tasmanian one was now forced to shut also. In most places only baby scallops were found, requiring at least 3 years to reach legal size and sufficient numbers to fish.

“The dilemma was that there were so many permits still current that industry had the capacity to fish out any beds discovered and opened. It was still primed for the boom-bust cycle,” Haddon says.

Changing fishermen from ‘hunter/gatherers’ to ocean managers who husband their livestock has never been a straightforward process. Knowledge, pride, tradition, experience, technology and self-image all come into play. So does competitive instinct – the powerful urge to catch something before the next fisher does.

Haddon considered the solution lay in detailed spatial management of the scallop beds, opening a few when they were ready to be fished, and leaving most others to mature. It also lay in securing agreement among fishers this was the right way to go.

“If the distribution of scallop beds is known, and we know the average size and approximate abundance of scallops in each bed, then it is possible to plan the harvest of each bed through time with the aim of ensuring a fishery each year, focussing on the biggest, most valuable scallops.  This spreads the boom years across many more years and limits us to more sustainable catches,” he says.

Under the new system scallop beds become “paddocks”, to be harvested when the crop is ripe. Besides providing steady income for fishers this also ensures continuity for jobs, industry infrastructure and market supply and demand.

“Leaving large amounts of scallops undisturbed increasing the chances of further successful spawnings and large scale settlement – so we can gather bigger and better harvests in future,” he adds. “It focuses dredging effort on small areas so that any negative effects are localized and there is time for seabed recovery before further dredging occurs.”

The downside is that to properly manage a resource you cannot actually see, there is a huge need for accurate information – far more than can be gathered by random sampling. The answer was a scheme in which fishers themselves ran surveys, searching for and characterizing scallop beds in scientifically credible way. These industry-mediated surveys were run along the Tasmanian east coast and into Bass Strait, with flotillas of up to 11 boats steaming in a line across the beds, recording precise details of their shots. The surveys involved the skippers and crews of the vessels Anita, Brid Venture, Brid Voyager, Christa Leanne, Dell Richey II, EJ Fairnie, Karmin, Petuna, Soluna, Suncoaster II, Tara Lyn, and Waubs Bay.

They found some beds clearly on the way to recovery, others still depleted from the hammering they received up to 20 years ago - which shows how long recovery may sometimes take.

The delight for Haddon is the wholehearted way today’s scallop fishers have embraced the new approach. “Initial distrust and suspicion of the strategy has now been almost fully replaced with enthusiastic support and participation by industry members. They’re making their own recommendations designed to increase the value of the product: for instance in 2006 they delayed the start of fishing even though the season had officially begun, purely to let the scallops put on condition and become more valuable. “

Catches are modest compared with the boom years – around 700 tonnes of scallop meat in total (4000t in the shell) – but there is every sign that this will grow as more beds come back from the effects of the boom/bust era.

Haddon makes the point that scallop dredging is not nearly as destructive of the seabed as the public seems to think: “the seabed where scallops reside is often rather sandy and featureless, and scoured by powerful currents which stir it up far more. It changes all the time through natural forces, and populations of sea animals shift constantly in space and time.”

However, the new approach of harvesting only those “paddocks” where the scallops are well-grown will limit the impact of dredging to particular areas and a single season, allowing several years for the site and its biodiversity to recover.

Today the scallop industry is an example both for Australia and the world of what can be achieved in sustainable fisheries management, he says. “You’ve got strong industry participation in managing the resource, an effective harvest strategy based on real information, steady economic returns, benefits to employment and to consumers and minimum disturbance to the environment,” he concludes.

The growth in trust between fishers, fisheries managers and scientists has produced what Patrick Hone, CEO of the Fisheries R&D Corporation sees as proof of environmentally sustainable development (ESD) in action. “The fishing industry’s performance in ESD today is a good deal better than the Australian community’s current perception of it – and the scallop industry is an excellent example of what is being achieved. This is a message we have to get across more widely.”

Industry-mediated surveys are examining the scallop beds timetabled for opening this year. These will ensure the scallops are of a good size and in market condition. Malcolm Haddon says it promises to be another good year in the Tasmanian scallop fishery.

Julian Cribb is adjunct professor of science communication at the University of Technology, Sydney and edits R&D Review and ScienceAlert.