Supplies have also been disrupted, with no petrol available by Friday night. Pubs have also been running out of beer.
The failure of an engine last Sunday on the 29-year-old MV Caledonian Isles, the principal ferry on the main Ardrossan-Brodick route – one of CalMac’s busiest – will leave it out of action until 3 May.
A substitute vessel, the 38-year-old MV Isle of Arran, can only carry half as many vehicles, with CalMac scrapping bookings and most drivers being forced to queue on a first-come-first served basis.
Ironically, the Isle of Arran was built at the Ferguson Ailsa shipyard in Port Glasgow, now Ferguson Marine, where the Glen Sannox is under construction to take over the route but not now expected to be finished until next spring – five years late.
CalMac has drafted in a second ferry to boost capacity on the other Arran route, between Claonaig on the Kintyre peninsula and Lochranza, which involves a 125-mile trip from Ardrossan.
The breakdown has again exposed the increasing fragility of Scotland’s west coast lifeline ferry links due to CalMac’s ageing fleet and increasing demand fuelled by fare reductions and the lifting of Covid travel restrictions.
Timothy Billings, a Conservative councillor and candidate for Arran in the North Ayrshire Council election, and a former island hotelier, said: “At this time of the year, the ferry is normally full to capacity so the loss of the Caledonian Isles is impacting every aspect of life on Arran.
"The biggest issue is Arran is getting a reputation of being a place which is difficult to visit and do business with.”
The National Trust for Scotland, which owns Brodick Castle, the island’s most-visited paid attraction, reported a significant fall in numbers.
A spokesperson told Scotland on Sunday: “The key impact has been on visitor numbers, which we estimate are down around 40 per cent.
"We were expecting around 2,200 this week and it looks like we will welcome 1,300-1,400.”
Isle of Arran Distillers said distillery visitors had halved to 120 a day, while a malt shortage had forced a 12-hour shutdown.
Auchrannie Resort in Brodick, the island’s largest hotel and leisure complex with 129 rooms and self-catering, said it had also been hard hit.
Linda Johnston, its co-founder and executive chairperson, said: “Occupancy is approximately 15 per cent down on where it should be over the next eight days.
“We have had cancellations of 5-12 per cent for each evening over the next week and this may rise further.
"Visitors are worried as the ferry is operating on a turn-up-and-go basis.
"However, Caledonian MacBrayne do seem to be managing to cope with volumes of traffic on the Ardrossan to Brodick route, albeit with some delays.”
Simon Hunter, from Northumberland, who has holidayed on the island annually for nearly 50 years and had booked a B’n’B this weekend, said: "If travelling hundreds of miles, you need to know you are going to get on the ferry you booked.
"The situation is getting worse.
"Last year, I went to Arran in August but my booking was cancelled on the main ferry so I had travel around to Cloanaig.
“When I went in October, the ferry was off again, so I had to go via Cloanaig again.”
Mai Lawrence said: "It is horrendous. We are very regular visitors as we have a caravan in Cordon.
"We have never experienced such a terrible service.
"How awful for all the businesses here after two years of Covid.
“All of this disruption is making Arran a place to avoid as people are afraid they can’t get home again.”
However, tourist chiefs are desperate the poor publicity will not deter visitors.
Sheila Gilmore, chief executive of VisitArran, said: "It's all been very negative and businesses are getting cancellations, so we need to be wary as this impacts on the island economy and community.
“There are boats. People need to come.”
Arran SNP councillor and candidate Tony Gurney said: “It is important to stress there is still a ferry service to Arran and the island is very much open for business.”
Other firms affected have included shops and fuel stations, even though such deliveries take priority on sailings.
George Lammie, who runs filling stations in Brodick and Whiting Bay, rationed drivers to £20 of petrol before supplies ran out on Friday morning.
He said no petrol would be available on the island over the weekend unless there was another delivery.
Lammie said tankers were given priority to board ferries to Arran but had to take their place in the queue on return sailings.
He said: “It’s a major problem, on top of the hassle I get from people about the price of fuel.”
Clair Reeves, who runs The Bay Kitchen and Stores in Whiting Bay, said: "Our shop, which has traded for 100 years, has never faced business uncertainty like this.
"Covid was a breeze in comparison.
“Our supply chain is severely compromised.
"We are dealing with missed deliveries, upset customers and inept decision-making about prioritisation – camper vans let onto the ferry rather than our wholesaler’s truck.”
Sam Bourne, chairman of the Arran Ferry Action Group, said: “It’s a very, very challenging time for the island.
“Businesses are considering closing, or have already closed, as they have no stock and cannot get supplies."
Marc Crothall, chief executive of the Scottish Tourism Alliance, said: “It’s an absolute disaster and a huge challenge.
"Such transport fragility causes much concern.”
CalMac managing director Robbie Drummond said: “We appreciate the impact on islanders and visitors alike and we are doing all we can to help passengers complete their journeys.
"We apologise to our customers for the inconvenience caused by this technical breakdown and can assure them that we are doing all we can to minimise the impact.”