Cloak any landmark, bar the occasional cormorant marking time atop a buoy, but the boat's captain is not fazed.
" It's like hunting bears with a blindfold. "This is how Matt Varndell describes his day at work fishing for clams. However, given its political dangers, economic risks and the uncertainty that still haunts the process, "blindfolded bear hunting" sounds like a metaphor for Brexit and the UK government's attempts to leave the European Union (EU).
But from seabed to table top, the wider economic "food chain" of British seafood – catching, trading and serving fish – highlights the Gordian Knot of issues that have bedeviled the UK's efforts to divorce from the EU.
Varndell has worked at sea since he was a teenager, when his father first took him out on his boat, the Versatile.
"It was the freedom of fishing that attracted me to this job. The unknown," he said. "Being at sea, the sea water gets into your blood."
This is not a career for the faint-hearted, however. Just one or two clams every morning on his floor along the sea floor. A good tow can only draw up and boxes. At the end of the day he split his catch 75-25 with his deck hand, Richard, netting between £ 400 and £ 450 ($ 522- $ 587) in total.
As he zigzags his boat through the waters near Portsmouth, Varndell rails at the suffocating hold he feels regulations have on his work.
"The legislation has gone beyond reasonable and the fleet is getting smaller and smaller by the year," he said.
British inshore fishing is regulated by local Inshore Fishery and Conservation Authorities (IFCA), which state their aim as balancing "social, environmental and economic benefits to ensure healthy seas, sustainable fisheries and a viable industry." Although a UK body, they enforce EU directives on managing the environment.
"Of course fishing has to be sustainable otherwise I'm out of business," Varndell said, but added that IFCAs are more focused on conservation than on balancing fishermen's needs with the environment.
"It makes a very difficult job almost impossible."
Varndell refuses to blame European fishermen. "If I had the opportunity and had enough to go to France and exploit their fishing grounds, which yielded a lot more than what my fishing grounds do, I would do it," he said.
From the coast, fish flows through the hands of traders like Eric McLeod in British fish markets. His Portsmouth-based firm, Viviers, buys fish from local fishermen along the southern coast as well as from abroad.
"I don't sell fish just in the UK. We export mainly to Spain, France and we used to sell to Italy," he said.
McLeod has long thought that EU membership was bad for Britain, while protesting at sea when the UK joined the European Economic Community in 1972.
But for others, Brexit is a worrying prospect.
If the UK enters a new customs agreement with the EU, it is possible to deliberately delays where goods currently flow unimpeded by inspections, new checks and paperwork, especially if the system is newly introduced.
"If [UK traders’] product is very fresh or even still alive, any delays reduce the freshness, the self-life and therefore the value and, if the delay is long enough, could potentially render the product valueless to the purchaser, "said Hazel Curtis, Corporate Relations Director at Seafish, a public body supporting the UK seafood industry.
McLeod shrugs off such companies, buoyed by his experiences dealing with EU fish traders. "They don't want to be trading with the UK," he said. "If another country wants our fish and I'm sure they'll have to pay the increased charges." "I think there's been too much political argument within all parties," he said. "The plates of Cornerstone restaurant, tucked away in a gentrifying corner of post-industrial."
London and specializing in seasonal produce, is the end of the journey for some British fish.
Therefore, Tom Brown, the establishment's young chef-owner, feels the ripples of concerns upstream the fish "food chain." Brown buys all of his seafood directly from local merchants or fishermen in Cornwall and is very conscious of how difficult life is for people like Varndell under EU regulations.
But potentially increasing import taxes driving up the price of the foreign currency and a post-Brexit financial fallout hitting customers' pockets weigh heavily on the restauranteur.
"We're a small, family-operated-style business. t have anything else behind us to absorb any sort of massive hit, "Brown said.
" If people don't have a lot of disposable income, what's the first thing that goes out the window? Eating out at restaurants. "
But one possible Brexit side effect could quite literally change the face of his business.
"All of the staff we have that work on the front of house are non-British citizens," Brown said.
"Jobs in the front of house are, by British people, seen as a stopgap, something that you do at university or looking for another job. On the continent it seems much more like a career choice, "he said.
"A restaurant manager is France is considered the same way as a bank manager so it's taken very seriously."
"If we had to help all our staff pay tons of money in, if we had to leave a lot of staff really quickly it would be a massive hurdle for us to get over in a restaurant," he said.
"The thing is more the uncertainty," Brown said. "I mean know as much as the government about Brexit, which is nothing."
With just over a month to go until "Brexit Day" – Britain's planned departure from the EU on March 29 – uncertainty stains what The EU-UK divorce will actually look like, how it will work or whether it will happen.
From port to plate, wading through fishing rights, trade taxes and immigration controls, looking at British seafood it's obvious.