They also demanded compensation for the damage the action was having on their trade and to the reputational image of the islands.
The strike due on Friday has been called by the RMT union despite new talks to be held on Monday to try and resolve a dispute that badly hit west coast ferry services last week.
Caledonian MacBrayne and the RMT union are meeting in an effort to resolve the row over job security and pensions.
But reacting to the news of the new action, Ian Fordham, chairman of Outer Hebrides Tourism, said the Scottish government should intervene to halt the action which was crippling businesses.
“We are dismayed at the prospect of a further strike this week, just as the industry was getting back to normal after the last action,” he said.
“Businesses have already seen significant cancellations and losses from the last strike, which comes on the back of the five week disruption to the Stornoway – Ullapool route, and the long standing concerns over the inadequate Mallaig – Lochboisdale trial service.
“We call on the Scottish Government to intervene and ensure there are no further strikes, and also to establish a proper and fair mechanism for compensating both visitors and businesses who are out of pocket as a result of the industrial action.
“The compensation currently offered by Calmac only goes part of the way to helping people who have lost out, and we repeat our call for a proper scheme to be established immediately.”
Cal Mac’s managing director, Martin Dorchester said:”We are extremely disappointed that the RMT has chosen to continue with strike action. The best way to protect the existing terms and conditions of its members is to work with us to ensure we win the Clyde and Hebrides Ferry Service contract and this action is damaging.
“We are anxious to avoid any more disruption which is not in the best interests of our employees and the communities we serve and would urge all our colleagues to turn out for work.”
The Transport Salaried Staffs’ Association (TSSA) has also sent out strike ballot papers to about 100 of its members who work for CalMac.
Two thirds of state-owned CalMac’s ferry services were cancelled last Friday week during a 24-hour strike by RMT members - the culmination of three days of action.