Rising out of the water, nets bulge with thousands of blue mussels.Pulled back to the dredging boat, they are emptied into a hopper and rinsed with water.They have just been harvested fresh from the bottom of the Menai Strait, the channel that separates the north Wales mainland from the island of Anglesey.On a blustery, damp morning, skipper Alan Owen guides the 43-metre Valente out of Port Penrhyn, close to the city of Bangor, towards the mussel grounds around the pier.“It’s windy today but we’re not jumping up and down as there aren’t big waves.

If Anglesey wasn’t there it’d be a different story,” says Owen.“Our geographical position makes this probably the best place in Britain for producing mussels,” he adds, pointing to the boat’s screen, where different colours display the areas where several companies are licensed to harvest the shellfish.“It’s because of the tidal exchange going through the Menai Strait, it gets up to six knots in the middle there,” he says.“You’ve got a massive volume of water exchanging both ways, bringing in the food and nutrients the mussels like.”It was these natural advantages that helped turn the eastern Menai Strait into the largest mussel farming area in Britain from the 1960s onwards, employing scores of local people including Owen’s father and uncle.

Over the years, as production increased, the vast majority of the mussels were sent across the Channel to Europe, where diners – especially in France, Belgium and the Netherlands – tend to eat a lot more shellfish.The UK’s shellfish industry is small and specialised, valued before Brexit at less than £12m a year, but one which is crucial for some coastal communities.Britain’s departure from the EU closed off most access to the lucrative European export market, and has all but ended the industry in the Menai Strait.Since Brexit, mussel production has collapsed from about 10,000 tonnes annually to just five tonnes in 2022, representing just 0.05% of the previous total.

The Valente is the last remaining mussel dredging boat at Port Penrhyn; the other three have been sold off or redeployed.The company which owns the Valente, Myti Mussels is the only one of four mussel fishing companies fully operating.It now just sells small quantities of molluscs to UK customers.There is, however, a glimmer of hope on the horizon in the shape of the “reset” deal between Keir Starmer’s UK government and the EU, announced in May.Britain’s shellfish exporters and other food producers are expected to be one of the main beneficiaries of the UK-EU reset, designed to remove the need for sanitary and phytosanitary (SPS) controls at the border, which formed part of post-Brexit trading requirements, along with health and veterinary checks and supplementary paperwork.

The administrative burden was one of the reasons for the collapse in exports from north Wales, resulting from longstanding EU rules concerning imports of shellfish including mussels, oysters, clams, cockles and scallops – collectively known as live bivalve molluscs – from non-EU member states.Molluscs caught outside the EU can only be imported to the bloc without treatment if they come from waters with the highest quality rating, while vessels from non-EU states are also not permitted to land live bivalve molluscs in EU ports.The waters of the Menai Strait are, like the majority of those in England and Wales, rated “class B” for shellfish production, which is assessed according to the levels of E coli detected in shellfish flesh.This means mussels from the area can be sold for human consumption provided they are either purified in an approved location, or moved for at least a month to “class A” water, or alternatively treated with heat.Some fishers believe that sewage outflows into the Menai Strait after heavy rain has not helped improve the water quality in recent times.

Mussels from “class B” waters can still be exported to the EU, provided they are first purified – or depurated in industry parlance – by being placed for a day or two in tanks of clean seawater which has been sterilised using ultraviolet light.This process is costly and can cause stress for the molluscs, reducing their shelf life and making them less attractive to European buyers.There isn’t a purification plant in Bangor, or indeed in the UK, that could handle the volumes of molluscs exported pre-Brexit.However, that should be about to change, as an Irish seafood company has fitted out a building next to Port Penrhyn, which is awaiting certification.This investment and news of the reset talks have given Owen hope that the local industry can be resurrected.

“The customers are still there,” he says.“Where we are situated, weather-wise, we are 100% reliable.If they pick up the phone and order, we deliver.”Sign up to Business TodayGet set for the working day – we'll point you to all the business news and analysis you need every morningafter newsletter promotionOwen’s son Martin followed his father into mussel harvesting, but the state of the industry means he has other ambitions for his grandson, Martin’s 12-year-old son.“We’ve taken him out on the boat a few times and he likes it, but he isn’t yet old enough to decide what he wants to do for a job,” says Owen.

“He has got the brains to go into something better.”Others are less optimistic about the industry’s future prospects.James Wilson is one of the owners of the mussel producer Deepdock.The business has stopped trading since Brexit and Wilson now runs a fish and seafood shop next to the port for part of the week, alongside teaching at Bangor university.“We tried every possible avenue that we could think of to try to secure some stable access to the EU market, but found a locked door at the end of it,” Wilson says, in between wrapping up fish fillets for customers.

He was initially encouraged by news of the reset talks, but given that any implementation of an SPS deal is unlikely to happen before 2027, Wilson worries it will be hard to restart significant mussel exports.The local mussel beds would also need to be repopulated.This requires very young mussels – called seed mussels – to be collected from other naturally occurring beds and laid in licensed areas, where they usually need a couple of years to grow to a marketable size.“There’s always uncertainty, particularly in respect of the juvenile mussels, the seed mussels, so we have natural variability associated with that,” Wilson says.“If you’ve got an input uncertainty with the seed, added to an output uncertainty as to whether you’ll be able to sell anything you’ve got on the ground, it’s just too much.

It’s a big investment, millions of pounds, to buy a boat, run it, crew it.You’ve got to have certainty.”Many other shellfish businesses around the UK are “on hold”, says David Jarrad, the chief executive of the industry body the Shellfish Association of Great Britain.“So much for a reset,” he adds, saying “the longer it takes [to implement an SPS agreement with the EU], the less chance there is that they will be able to start trading again.”He and many others believe the UK is missing out on a potential growth sector, supplying customers with a large appetite for British shellfish.

“The UK is located in the sweet spot for cultivating shellfish almost anywhere in the world,” Jarrad says.“Our aquaculture industry is minuscule in comparison with Spain and France and the Netherlands, even though we have a greater coastline.”A government spokesperson said: “We are focused on negotiating an SPS deal that could add up to £5.1bn a year to our economy, by cutting costs and reducing red tape for British producers and retailers.”Back at the fish shop next to Port Penrhyn, Wilson wonders whether a future SPS agreement could inspire a new generation of mussel fishers.

“Maybe if somebody with a bit more enthusiasm, a bit more energy, a bit of money comes in, then it might all happen.”