Eight o’clock on a slate-grey morning in Lowestoft, and there’s a force five blowing in from the east. “It’s going to be lumpy out there,” we are warned. Outside, the wind is razor-edged. The thermometer is showing 4C, but it feels more like -2, and we haven’t even left the quayside.

Our ride for the morning is Maximus, a 10-metre day boat owned by fishermen Chris and Steve Wightman. The brothers spend up to 150 days at sea each year, 12 or 14 hours each time. Today’s four-and-a-half-hour outing – a concession to us landlubbers – is a pleasure cruise by comparison. Beyond the harbour wall, the waves come in jagged volleys, lurching the horizon through 90 degrees. Fishing is a masochistically tough way of making a living.

Up front with the lads is Tom Aikens, the Michelin-starred chef and owner of Tom’s Place, Britain’s most talked about fish’n’chip shop. He has gone out of his way to ensure that his menu is environmentally sound, and while some of it isn’t familiar chippy fare – there’s gurnard and megrim sole – it all comes from sustainable sources, and Maximus is one of the boats certified to catch it.

Over the past year, Aikens has been out to sea off Newlyn, Hastings, Lowestoft and Peterhead to find out exactly where his fish comes from. “Doing a fish and chip shop, I could have come in for a lot of criticism,” he says. “I knew that I had to do it right. Fishing isn’t like farming: it’s easy for a chef to trot into a field and pat a cow. I wanted to experience the industry first-hand, to really understand the issues involved.”

Figures for the world’s dwindling fish stocks make depressing reading. More than half are at their biological limit, with another quarter overfished or depleted. The worst-case scenario suggests that if we don’t act fast, fish could be permanently off the menu within 50 years. But the picture isn’t totally bleak: some in the fishing industry are working hard to put their house in order. There are now 26 sustainable fisheries around the world that are certified by the Marine Stewardship Council, including handline mackerel fishermen in Cornwall and cod boats in the Bering Strait, as well as more than 60 others currently under assessment. Together, that’s 8% of the world’s catch.

“There’s a lot of fish now being caught in a totally responsible way,” Aikens says. “The people involved are passionate about what they do and want to make it work. I want to build up a network of fishermen that I and other chefs can use. Hopefully, I can help the fishermen make more cash along the way – currently, it’s Mickey Mouse money for what they do.”

Maximus is the first Lowestoft boat to qualify for the Responsible Fishing Scheme, a new BSI standard set up by the industry body, Seafish, to highlight and reward sustainable fishing practices. So far, 164 boats around Britain have qualified for the scheme – from trawlers to small day boats. The Wightmans use a method called longlining, by which four to six miles of baited lines are let out behind the boat and weighted to the seabed. They are left for a couple of hours before being wound back in, hopefully with fish in tow.

It’s far more selective than trawling, and only fish of a certain size are big enough to take the hooks. It also makes sense in terms of quality: the catch is gutted as soon as it comes over the side, so it remains sparkling fresh. On an average trip, the Wightmans might land 500kg of fish – mostly cod and rays – although today’s east wind brings us just five cod. The sustainable approach means extra work, but the hope is that the fish will make better prices as a result. Cod sells at the moment for about £1.60 a kilo. With fuel costs, bait and insurance, the fishermen need to make £2,000 a week to earn a wage of £200.

The level of regulation has changed radically in the past 30 years. In place of a fishing free-for-all, there are strict quotas on what fish can be caught and where. It’s not a level playing field – Spanish, French and Dutch trawlers are allowed to within six miles of the British coast – and one-size-fits-all rules mean that boats in areas with plentiful stocks often catch their entire year’s allowance of certain fish within a month. Tons of fish are thrown back dead simply because they don’t fit the figures. Many argue that if the quota system has given fish stocks around Britain a chance to recover, it’s only because it has forced so many boats out of business. But it is, at least, a base from which the fishing industry can move forward, and small day boats such as Maximus are likely to play an important role in its future.

Of course, we also have our part to play, and eating sustainable cod is a good place to start. But sustainability is only partly about where fish comes from and how it is caught. It’s also about the range of fish we eat. “There are huge numbers of fish that nobody’s eating,” says Aikens. “Coley, dab and pouting, for instance. Even mackerel and sardines aren’t as popular as they used to be. A few years ago, megrim sole was something you gave to the cat – but it’s actually great flaky white fish for frying and baking. The trouble is that it had no market value, because nobody knew about it. That’s down to chefs and down to consumers. In the end, the fishermen catch what’s popular. Changing our mind-set and asking for other fish can make a difference. Even Birds Eye do a pollock fish finger these days.”

For more information on the Responsible Fishing Scheme: rfs.seafish.org. Marine Stewardship Council: www.msc.org. Tom’s Place, 1 Cale Street, SW3; 020 7351 1806, www.tomsplace.org.uk

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