It’s been slow going for the Nova Star ferry service between Portland and Nova Scotia since its launch in May, but its operators say they’re encouraged by passenger volumes in August.

The company reported it carried 20,510 passengers last month between Portland and Yarmouth, Nova Scotia.

Additional Images A Nova Star ferry crew member collapsed and died Monday afternoon on the ferry's final trip of the season. 2014 Press Herald File Photo/Tim Greenway Related Headlines Nova Star ferry finds route for service this winter, then will return for second season

That’s an average of 331 passengers per one-way trip, a 53 percent increase from July, which had an average of 217 passengers per trip, and a nearly 200 percent increase over June, which had an average of 112 passengers per trip. The service began on May 15.

The August numbers, which were released Friday, are evidence that the business can and will succeed as more people discover the charm of Nova Scotia and the convenience of traveling on the Nova Star, said Mark Amundsen, president and CEO of Nova Star Cruises Ltd., in a news release. “We knew from the outset that it will take some time to build this route back to where it was 10 years ago, but we are very encouraged by our first year of operation.”

The operators of the Nova Star had predicted at the beginning of this year that it would carry 100,000 passengers, but at the end of August it had carried only 45,000.

Nova Star Cruises on Monday announced it was ending the season three weeks early and was offering refunds to 650 passengers who had already booked tickets on the canceled runs.

While the Nova Star has a capacity for 1,215 passengers, the number of cabins is limited because the ferry was designed for a much shorter trip, a three-hour crossing of the English Channel rather than a 10-hour trip across the Gulf of Maine, Amundsen said at a business gathering in Portland on Thursday. He said he would be pleased if the ship carries between 500 to 700 passengers per trip.

The ferry is more popular on the overnight trip from Portland to Yarmouth. In August, 10,913 passengers sailed on Nova Star from Portland to Yarmouth, and 9,597 made the trip from Yarmouth to Portland, for a total of 20,510 passengers for the month. Nova Star also carried 6,769 vehicles in August, including cars, motorcycles, RVs and commercial trucks. The company did not say how many commercial trucks it carried.

Using a $21 million subsidy from the Nova Scotia government, Nova Star Cruises has revived ferry service between the two ports, which was discontinued in 2009.

In 2002, two ferries, the Cat out of Bar Harbor and the Scotia Prince out of Portland, each carried 165,000 passengers to Yarmouth. But by 2009, volume on the one remaining service, the Cat out of Portland, had collapsed to just over 75,000, according to a 2012 report from Nova Scotia experts that examined re-establishing a ferry service.

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