IT is one of the smallest inhabited islands in the Hebrides which two years ago had a population of just 15 despite a worldwide competition aimed at attracting people to move there.

Now Canna, one of the most environmentally protected areas in the UK, is at the centre of fresh dilemma, over plans to build a large salmon farm just off its coast.

Mowi, the world's largest producer of Atlantic salmon, have submitted outline plans to install eight fish-farm cages to produced thousands of tonnes of organic salmon off the westernmost of the Small Isles archipelago, in the Scottish Inner Hebrides.

And the the National Trust for Scotland, which owns Canna has raised "significant concerns" about the development's effect on the "internationally important marine environment".

Scottish Natural Heritage (SNH), the government's conservation watchdog, has already raised its concerns for wildlife.

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And the trust which oversees the island's economic strategy, the Canna Development Trust has said the islanders were divided over the plans.

Plans show the cages would be 160 metres in circumference, said to be the largest installed in the UK. Salmon cages in Scotland are usually no bigger than 120 metres in circumference, and often smaller.

HeraldScotland:

Mowi, which plans to establish a shore base and pontoon near the pier on Canna, say the eight pens would cover nearly 16,300 sq metres, more than twice the size of a football pitch, with its moorings stretching across 222,000 sq metres of seabed.

The company says its neighbouring farms are operated near to the Isles of Rum and Muck.

The firm says it is likely that 10 people will be directly employed at the farm including a manager, two assistant managers and seven farm technicians.

But the NTS, which has been trying to repopulate the island which is currently a community of 18 people, has raised its worries although it has yet to make a formal response.

The NTS, tasked with protecting Canna from damaging developments, and bars private housebuilding there said: “As the conservation charity charged with the protection of Canna’s rich heritage, we have significant concerns about the potential effect on the internationally important marine environment.

"There could also be implications for tourism which is a major source of income for the island. We expect the regulators to ensure that any proposal in such a highly sensitive and protected area is supported by a comprehensive, evidence based assessment.

“We are in ongoing discussions with MOWI and the Isle of Canna Community Development Trust.”

HeraldScotland:

The government's conservation watchdog, Scottish Natural Heritage (SNH), has warned that Mowi's proposals could lead to "significant environmental effects" on the area's seabirds, porpoises and seals, and threaten rare marine life on the seabed.

In its initial comments to the Highland Council, it says the plan could have a significant effect on birds including puffins, red-throated divers and Manx shearwaters, which are also protected.

SNH say birds risk being entangled in farm nets and rigging, and that vulnerable species could be affected by fish faeces and uneaten food reaching the seabed.

"Particularly sensitive features in relatively close proximity include fan mussel aggregations; northern sea fan and sponge communities; white cluster anemone and horse mussel beds," the SNH said.

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Marine Scotland Science (MSS) said information from the west coast of Scotland suggests lice from fish farming can cause a risk to local salmon and sea trout.

The scientific division of Marine Scotland said in a response to the Highland Council that the Mowi development has "the potential to increase the risks to wild salmonids".

It said Mowi appeared to be aware of the potential impacts on salmon and sea trout and had undertaken to follow practices recommended in the industry code of good practice regarding containment and sea lice control.

It said that the applicant should submit full site specific details of the sea lice management strategies that are proposed for use on site.

Mowi has told Highland Council that the Isle of Canna community invited executives to discuss the potential of developing the site.

A community vote was taken in May which resulted in "the agreement to continue the project to EIA [Environmental Impact Assessment] stage".

The firm said: "Due to the sensitive nature of the location a second community vote will be taken following the EIA to decide whether the proposal will proceed to planning... stage."

Geraldine MacKinnon, chair of the Canna Development Trust, said further talks were ongoing with Mowi and that they were in close contact with neighbours on Rum and Muck, where Mowi already had two fish farms.

"People haven't made up their minds either way," she said. "It's a massive decision, so people just want to take their time."

Mowi said it was working closely with the islanders. "We continue to explore sites that are fit for today's salmon farming regulations and will work with communities that express interest in building a development."

A Mowi spokesman added: "Mowi and the residents of Canna have agreed to produce an Environmental Impact Assessment for further discussion regarding a potential aquaculture development.

"Mowi has recently announced its interest in following the recommendation of the recent Scottish Government inquiry that encourages off-shore, high-energy fish farming sites.

"Adding to the success of similar farm developments at the isles of Muck and Rum, we continue to explore sites that are fit for today’s modern salmon farming regulations and will work with communities that express interest in building a development that helps support local economies."