The first day of strike action by Serco workers on the North boats got underway as threatened today.
General secretary of the RMT Union, Bob Crow, said the strike was “rock solid”.
The dispute comes despite hours of intense negotiation between union leaders and Serco management yesterday, which failed to reach a resolution.
Serco workers are striking over plans by the company to shed up to 36 jobs.
Further strikes will be held over Friday 21st and 28th December, should subsequent talks come to nothing.
In those circumstances, services from Aberdeen will also face stoppages this Sunday, and on the two following Sundays.
In a statement Mr Crow said: “Despite gross intimidation by management of staff exercising their human right to withdraw their labour, the programme of strike action on Serco Northern Isles ferries, which began at midnight, is rock solid this morning.
“This fight is about safe staffing levels and the protection of skilled jobs and public safety in the teeth of outrageous profiteering. Serco should stop the threats and start talking.”
Serco NorthLink managing director Stuart Garrett said the strike was going ahead despite the company’s “best efforts” after the RMT failed to respond to its approaches yesterday.
“We remain disappointed that industrial action means ferry services to the Northern Isles will be disrupted this weekend and potentially over the festive period,” he said.
“Dialogue has been re-established this morning and Serco remains willing to communicate, as we have throughout.
“On the Hjaltland, currently weather-bound in Lerwick, only eight of the 41 crew members affected are currently participating in industrial action.
“We have worked hard to minimise disruption to our freight and passenger customers. We have been in touch with our freight customers with details of our amended timetable which maintains freight service continuity.
“We have also tried hard to contact all those booked on disrupted passenger sailings and advised them to transfer to alternative sailings.”
• Both the M.V Hjaltland crossing scheduled to depart Lerwick sailing for Kirkwall (Hatston Pier) and Aberdeen at 5.30pm today and the M.V Hrossey which was scheduled to depart Aberdeen for Lerwick at 7pm have been cancelled.