A pay dispute with officers was settled last year

Workers on the Clyde services voted in favour of industrial action earlier this month because they are demanding parity with crews in the Western Isles.

Management agreed to consider improved rates for staff on Clyde-going vessels - but said they were not prepared to accept the union's demands for pier hands to be included in the deal.

Last year a threatened strike by staff on the company's services in the Western Isles was averted.

At that time a Western Isles councillor, Donald McLean, urged CalMac to raise staff morale in an effort avoid future industrial action.

Officers' union Numast called off a planned four-day stoppage over a busy holiday weekend when they asked members to accept a package worth 5.75% over two years.

However, the agreement was only reached after an estimated �1m had been lost to the Hebridean economy through cancelled bookings from tourists and businesses.