FERRY campaigners have called on Nicola Sturgeon to tackle "anti-competitive and illegal" harbour charges isolating their rural community.

In a letter to the First Minister, Susanna Rice, convener of the Dunoon-Gourock Ferry Action Group, said their members in Argyll were "not prepared to be left dangling without a proper ferry service any longer" and criticised "excessive harbour charges" set by Caledonian Maritime Assets Ltd (CMAL).

A long-standing local campaign has been waged in Dunoon for the return of a service similar to that previously operated by CalMac. But in 2011 ministers tendered the route as a passenger-only operation, now operated by CalMac's sister company Argyll Ferries.

A subsequent exercise was undertaken by the Scottish Government to assess the potential interest among operators of running a car ferry service between Gourock and Dunoon town centres, without the need for additional subsidy, ahead of the new ferry contract being awarded. The new term is due to begin on July 1 2017.

Six companies responded but only one said it would run a car ferry, and then "only if Scottish Government bore revenue risk for the vehicle service".

The Scottish Government has stressed that any vehicle component would be run entirely at the operator’s commercial risk.

However, Ms Rice said the action group had identified a private operator willing to consider commissioning new car ferries, a potential shipbuilder willing to build the new vessels, and private finance to fund the new ships.

But she added that their efforts were being hampered by delays in Transport Scotland publishing an Invitation to Tender, adding that the situation was exacerbated CMAL - the public body which owns Gourock harbour - planning to charge pier dues and berthing charges of £3 million per annum.

She said: "This is more than five times the operational cost. We have raised our concerns at excessive harbour charges for over three years now without success. Indeed, when we initially raised our concerns at excessive harbour charges, CMAL responded by increasing harbour charges.

"We wrote to you, Derek Mackay and Alyn Smyth MEP, a solicitor with qualifications in European law, pointing out that the proposed harbour charges were anti competitive and contrary to Article 82 of the EU Treaty. But still we cannot get satisfaction."

A CMAL spokeswoman said the charges affected a "very small number of customers" and were in line with the revenue required to operate, maintain and improve the west of Scotland's harbours and compliant with EU competition law.

She added: "Without detail of exact vessels and service frequency, CMAL is unable to comment on berthing charges for a proposed privately operated service on the Gourock to Dunoon route.

A spokesman for Transport Scotland said the ferry service contract would be "awarded in good time" and that Transport Minister Derek Mackay would "take another look" at the harbour charges following concerns raised by the action group.

The spokesman added: “Scottish Ministers have worked closely with the Gourock Dunoon Ferry Services Steering Group to consider the options available for tendering this service. Ministers have concluded that the next contract should be tendered on the basis of a passenger-only subsidy, whilst also encouraging bidders to provide an unsubsidised vehicle service at their own commercial risk. We will undertake a competitive tendering exercise to this effect in 2016."