The Cambo oil field isn’t the only controversy in the waters off Shetland. Island fishermen say Spanish and French-owned boats are destroying marine ecology, with miles of discarded gillnets entangling and drowning seals, birds and other sea mammals before falling to the sea bed to ‘ghost-fish’ for eternity.

And Brexit hasn’t fixed the problem - it’s only got worse. Scotland’s Remain-voting majority may not automatically feel much sympathy for deep-sea fishermen who generally bucked the Scotland-wide trend to back Brexit. But muttering ‘we told you so’ won’t help the marine environment, or island incomes as employment in the oil industry starts to dwindle.

Shetlanders were promised competition with foreign-owned boats in local waters would cease when Britain ‘took back control’. But, French and Spanish-owned boats are still there, ironically in greater numbers post-Brexit because of the abundance of fish.

Gillnets are the issue - massive vertical curtains of mesh, hanging from floats - although their use is perfectly legal beyond the 12-mile limit. But the scale of their operation in the deep seas is eye-watering. According to one trawlerman, “They work in wolf packs covering 5-600 square miles of sea with 12-24 vessels. Each one has 5-10 nets. Each net is seven miles long and they operate 24/7.”

Which means there’s no room for anyone else - particularly galling in light of the pre-Brexit pledges that locals would be given the upper hand.

But it’s hard to complain. Some of the Spanish-owned vessels are UK registered (flag ships) and the UK government negotiated access for other foreign boats in return for Brexit concessions.

Maddened local fisherman know they’ve been played.

The UK’s Maritime and Coastguard Agency (MCA) could clamp down on the discharge of garbage into the sea, but they won’t.

Marine Scotland could investigate ghost fishing, but they don’t. They say “Marine Scotland officers proactively report incidents through our intelligence system to the MCA and we periodically remind vessels of their obligations [under international pollution regulations] working closely with the MCA when it becomes aware of any safety-related incident.”

Since neither agency will engage with the problem, trawlermen are battling it out for themselves. As a result, the area 60 miles west of Shetland has become “the Wild West” according to local newspaper editor Hans J. Marter.

He researched an incident in June 2020 for the Shetland News based on video footage which appeared to show the Spanish-owned but German registered gill-netter trying to run a rope through the propeller of a locally-owned boat. Its skipper James Anderson told the paper: “They now quite boldly tell us we need to move, and when we say we won’t, things like this happen.”

Both the MCA and its German equivalent condemned the dangerous activity revealed in the video which, they said, could have had serious consequences. But nothing happened. Now, Hans says, he can hardly run stories about seven-mile-long gill nets being found abandoned at sea by Shetland trawlers because it’s so commonplace.

Another veteran of the Shetland fishing scene says “Trawling tows are being destroyed catching gill nets and some gillnets are destroyed when local trawlers deliberately sail through them. The big problem is that gillnets and trawlers cannot both fish in the same place. It’s a real mess all round.”

But a local fisherman with reams of video evidence, disputes the idea that trawlers are to blame for the damaged gill nets.

He says the massive ships - at sea for 4-6 weeks at a time - lack the storage space for the rubbish they generate, since most of their holds are full of frozen fish. Worn-out gillnets should be returned to port for disposal. But without the storage space, they are dumped at sea, along with the rubbish.

He’s watched gillnetters dock at Lerwick, pick up supplies and kilometres of new gill nets but deposit no old ones or any sacks of rubbish. And he says the abandoned gillnets he’s found have no floats or weights attached – these expensive parts can be reused, so they are cut off - further evidence the nets have been deliberately discarded.

Of course, this is hard for onlookers to verify. That’s where government agencies should come in. Except by all accounts, they don’t. Shetland fishermen say patrol vessels are reluctant to board foreign boats in case they create an incident, focusing attention instead on local boats.

So, whose rights should prevail, how long before there’s a serious accident at sea and how serious were the commitments to enhance marine environment protection made six short months ago at COP26?

Ecologist and journalist George Monbiot - no friend to the deep-sea fishing industry - has drawn attention to photographic evidence “so disturbing I can scarcely bear to look: drowned seabirds, decapitated seals and fish and crustaceans of many species, which died a long, slow death”.

He says no data or studies have been produced by Marine Scotland to show where discarded commercial fishing gear is coming from, even though it accounts for 90% of the ocean plastic collected by beach cleaners around the Highlands.

So, what’s the solution? Some local fishermen want gillnets banned completely, although with a large mesh size to let immature fish escape, they cause no more damage than trawling operations when checked regularly and deployed safely.

Some want the size and scale of the vast Shetland gillnets and the number of boats working in tandem to be controlled. All want more checks by the marine agencies of the Scottish and UK governments.

Marine campaigners OpenSeas believe this is a contest between two equally damaging fishing methods. But the local Green council candidate backs the trawlermen’s campaign. And since nets should be traceable to boats, it wouldn’t be hard to spot patterns of deliberate disposal if any government agency was minded to act.

But seemingly, they’re not. Is marine pollution too low a priority for Holyrood and the threat to marine safety too awkward a problem for the Brexited British Government to even acknowledge? It certainly looks that way.

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