Ms Mary Ferns is the managing director of the South East Shellfish Co-operative, set up to commercialise the mussel beds in the Suir estuary, which has a membership of 41 fishermen. In 1992, its first year in operation, 1,000 tonnes of seeds were taken from the Irish Sea and relaid in the estuary. The biggest harvest has been 2,500 tonnes and the biggest annual turnover was around £1 million (€1.27 million). At the other end of the scale, Marine Harvest in Fanad, Co Donegal, has a turnover of around £19 million a year and employs 170 people. Started in 1979, it has been a profitable enterprise since 1984. It's a subsidiary of Nutreco, an international feed-compounding company.

Marine's core business is salmon farming. Its processing plant primarily handles its own produce but, increasingly, handles salmon from other sources because of tightening food safety regulations.