FISHERMEN are facing prosecution for allegedly breaching a ban on scallop dredging designed to protect a wealth of seabed wildlife off the west coast of Scotland.

The Scottish Government’s marine watchdog has seized dredging gear and submitted a report to the Procurator Fiscal accusing fishermen of illegally scraping the sea-floor for the lucrative shellfish in the Firth of Lorn, a large nature conservation area south of the island of Mull.

The move comes in the wake of new evidence that an eight-year ban on scallop-dredging in the firth has been ignored by fishermen. At the same time, fierce arguments between the industry and conservationists over a planned new system of marine protected areas are coming to a head.

Over 200 square kilometres of the Firth of Lorn, which contains the famed Corryvreckan whirlpool, are designated as a Special Area of Conversation (SAC). This gives legal protection to rocky reefs and the endangered and unusual marine wildlife they support, such as sponges, seafans, featherstars and coral.

Scientists say that scallop dredging, which pulls toothed rakes across the sea-floor, can inflict serious damage to wildlife. In 2007 the Scottish Government banned all scallop dredging in the Firth of Lorn SAC.

But scallop dredging in Scotland is a £30 million industry that can earn individual boats hundreds of thousands of pounds in a few months. And now government inspectors say they have caught one boat breaking the rules.

The Firth of Lorn has been monitored by satellite, aerial surveillance and at sea by the government’s Marine Scotland Compliance agency. “Over the last twelve months four intelligence reports of activity in the closed area have been received, all of which have been followed-up and investigated,” a Scottish Government spokesman told the Sunday Herald.

“In the past month a report has been submitted to the Procurator Fiscal after enforcement officers detected a vessel allegedly fishing illegally in the Firth of Lorn SAC. The fishing equipment was also seized under powers granted by the Marine (Scotland) Act 2010.”

The government declined to name the vessel, but confirmed that it was accused of illegal scallop dredging. The fiscal is now investigating and will decide whether or not to launch a prosecution.

Conservationists welcomed the move, but pointed to evidence that the scallop dredging ban in the Firth of Lorn has been breached for years. A map of vessel movements in the firth logged by satellite and recently published by the Scottish Government showed “high” and “very high” densities of scallop dredging between 2007 and 2013.

According to the umbrella group, Scottish Environment Link, this suggested “possible breaching of the existing regulations, which needs urgently addressed.” This was reinforced by news that a report had gone to the fiscal, argued Calum Duncan, convenor of the group’s marine taskforce.

“The report of alleged illegal fishing in the Firth of Lorn further underlines the need to effectively monitor scallop boats in places where they are prohibited from dredging,” he said.

“In April last year, vessel monitoring evidence prompted a dredging ban in Loch Alsh near Skye to protect fragile reefs. Safeguarding these habitats is vital for the health of our seas.”

The Scottish Fisherman’s Federation, however, disputed that there was a high level of scallop dredging in the Firth of Lorn. The monitoring system only showed that boats were present, not that they were fishing, and so was “inaccurate and open to misinterpretation”, said the federation’s chief executive, Bertie Armstrong.

Scottish Environment Link was guilty of “constructive mischief”, he claimed. “It is really disappointing that they have chosen to draw conclusions which are not supported.”

But David Ainsley, a marine biologist who runs a wildlife watching business in the Firth of Lorn from Clachan Seil near Oban, argued that dredgers shown circling islands in the area could not be explained as just passing through. “It is of great concern that the current policing system is not effective at preventing illegal fishing in protected areas,” he said.

Conflicts over the Firth of Lorn have surfaced as the Scottish environment minister, Richard Lochhead, prepares to introduce a new system of marine protected areas (MPAs) around the coast. Angrily opposed by the fishing industry, these are seen by conservationists as a small but significant step forward in preserving wildlife.

Last week the Scottish Parliament’s environment committee wrote to Lochhead asking him to postpone issuing six statutory instruments bringing MPAs into force. They were due to be laid before parliament on September 17, but MSPs under pressure from the fishing industry want them delayed until after they have heard new evidence on September 23.

This has been welcomed as an important move by the fishermen’s federation. “There is huge concern and dismay in our west coast fishing communities about the way the surprise proposed measures will impact upon livelihoods,” said Armstrong.

Scottish Environment Link, however, contended that well-managed MPAs were vital to protect marine life. “Sustainable fishing can continue – and thrive - inside MPAs,” said Duncan. “But the time is long overdue to reform the way we manage and monitor all inshore fishing activity, inside and outside of MPAs.”