BAR HARBOR – A deal in the works to provide high-speed car ferry service between Portland and Yarmouth, Nova Scotia, would reduce the number of trips originating in Bar Harbor to about four a week.

The Cat, operated by Bay Ferries Ltd., travels between Bar Harbor and Yarmouth at least once a day during the mid-May to mid-October season.

If a deal between Bay Ferries and the city of Portland is made final, the ferry would run from southern Maine to the Maritime Provinces three days a week and from Bar Harbor to Yarmouth on other days.

The executive director of the Bar Harbor Chamber of Commerce was guardedly optimistic Tuesday about the proposed changes.

“In the best of worlds we’d have The Cat seven days a week out of Bar Harbor and also out of Portland several days a week,” said Costas Christ. “I’m not 100 percent sure that this would be a negative impact. … I think the important thing here is that the Bay Ferries hub of operation will remain Bar Harbor.”

A Bay Ferries official said the company believes the addition of a southern Maine port would help, not hinder, midcoast Maine tourism.

“We think that we’ll be able to serve both markets and still serve the needs of the traveling public,” said Risteen Masters, marketing director for Bay Ferries. “In a way, we’ll be making it easy for people to be traveling the coast of Maine.”

She said Tuesday that the company has been pulling together what it has dubbed “triangle packages,” or tours aimed at clients who want to travel from Portland to Yarmouth to Bar Harbor or the reverse.

“We think it’s going to be a great new product offering,” she said.

The Cat holds up to 900 passengers and cruises at 55 mph, making the trip from Bar Harbor to Yarmouth in less than three hours and from Portland to Yarmouth in roughly five hours.

If the deal is approved by the Portland City Council, it would replace the Scotia Prince, which served the city for 35 years until it abruptly canceled service last spring. Those involved in negotiations expect the deal to be approved this month.

Business this season on the Bar Harbor-Yarmouth run has been good, according to Masters.

“Our traffic’s been up over last year,” she said.

Citing the high cost of fuel and midseason market conditions, Masters said that the ferry cut back on the number of trips to Canada at the beginning of September, dropping from two a day to one.

Between 25 and 30 full- and part-time employees work out of the Bar Harbor terminal. If trips are reduced from every day to four days a week, it is uncertain if the number of local employees would be affected.

“I don’t know that there would be a reduction in the number of staff,” Masters said. “I suppose some people’s hours would be cut back.”

The Associated Press contributed to this report.