THE arrival of the MV Renfrew Rose in the Cromarty Firth this week was warmly welcomed locally. In a former life the 30-year-old vessel was part of the Renfrew Ferry operation on the Clyde, carrying passengers between Renfrew and Yoker until 2010.

Since then she has been taking passengers and three cars at a time between Burtonport on the Irish mainland to Árainn Mhór, the largest inhabited island off the west coast of County Donegal.

Now she is to take over one of the ancient ferry routes in Scotland, albeit a rather unheralded one in modern times.

It runs between the community of Cromarty on the north east tip of the Black Isle and Nigg on the Easter Ross peninsula, near where King William the Lion built Dunskeath Castle in 1179.

It became known as the King’s Ferry, and James the 4th used it on his frequent visits to the shrine of St Duthac in Tain.

It got a new lease of life with the establishment of the Nigg oil fabrication yard in 1972 and today it is the last car ferry connecting two points on the east coast of the Scottish mainland.

But last summer it didn't run because of a dispute between the previous operator and the local harbour trust concerning overnight berthing. A big hole was left in the local economy, as it carried 17,000 vehicles and passengers in the summer of 2014, including cyclists as part of the part of the National Cycle Network Route 1.

The slipways appeared forlorn as fears grew it could be the end of the ferry. But following a tendering process the Highland Council awarded a contract to Highland Ferries, which runs the Fort William to Camusnagaul passenger route at the head of Loch Linnhe.

While the arrival of the Renfrew Rose was the cause of celebration in Cromarty, the community along with many others in the area say they are faced with a bigger challenge.

They await a pronouncement by the UK Maritime and Coastguard Agency (MCA) on an application from the Cromarty Firth Port Authority (CFPA). This is for a licence to transfer nearly nine million tonnes of crude oil a year oil between tankers at anchor at the mouth of the firth.

Many fear “the catastrophic impact” of an oil spill on the Moray Firth dolphins, designated environmental sites, bird sanctuaries and the vital tourist industry.

The port authority calculates that it could be worth £750,000 to the economy of the area, although there is no mention of any direct jobs.

But the local campaign Cromarty Rising has members expert in environmental consultancy and the oil industry. They are known to be preparing a detailed financial analysis of the value of the ecosystems of the Cromarty and Moray firths, to highlight what is at stake in the event of an oil spill. Their figure is already well over £100m, and still rising. The hope is new environment secretary Roseanna Cunningham and the European Commission take a closer interest.