A political dispute over the ownership of a cross-border waterway has triggered the rapid spread of unauthorised oyster farms and needs to become a priority for government, MPs have heard.
Sharon McMahon, of the Loughs Agency, told the Northern Ireland Affairs committee that Lough Foyle oysters could be worth £20 million.
The industry in Lough Foyle is un-regulated due to the political dispute over who owns the waterway, which straddles the Irish border.
The authorities currently have no power to regulate or control the spread of the oyster farms which have increased dramatically in recent years.
Ms McMahon said on the Northern Ireland side, the Department of Agriculture, Environment and Rural Affairs (Daera) issued notices, but she said there are more oyster tables on the Inishowen side in the Irish Republic.
She described the situation as “quite urgent” and said it “should be a priority”.
The public evidence session was held in Newtownards, Co Down on Thursday as part of the committee’s investigation into the fishing industry and potential impact on it from Brexit.
Prior to the session, five MPs visited the Co Down fishing port of Portavogie.
The fishing industry is estimated to support 900 jobs in Northern Ireland, mainly in Kilkeel, Portavogie and Ardglass in Co Down.
Conservative chair Andrew Murrison - along with the DUP’s Ian Paisley, Kate Hoey of Labour, Tory Robert Goodwill and Jim Shannon of the DUP - also heard evidence from two fishermen and a representative of Lough Neagh eels.
Andrew Orr, a third generation fisherman, told the committee there is already a hard border at sea, as well as crippling restrictions, high costs and a lack of labour which is leading to scores of small boats being sold.
He told the committee that he hopes Brexit, “if done properly”, could rebuild the fishing industry.
He said their larger boats are not allowed within 12 miles of the Irish Republic’s waters and small boats not within six miles.
Jimmy Kelly, who runs a small fishing boat in Co Down, agreed, adding that if it was not for whelks the small boats would have had a “very tough year”.
Both men also spoke of the challenge in getting crew for boats and said they were reliant on workers from the Philippines and Lithuania.
They suggested incentives to encourage young people to consider a career in the industry and also education courses.
Pat Close, of Lough Neagh Eels, said they are concerned about the impact of Brexit on their export trade.
He said some 80% of what they produce goes to the Netherlands, with the remaining 20% going to Billingsgate in London for the production of jellied eel.
Speaking after the hearing, Mr Shannon said Brexit offers enormous opportunity for fishermen.