Citing mounting debts and lackluster revenues, the Honolulu Symphony said it will file for bankruptcy protection and may lay off half of its musicians.

The 109-year-old symphony, which bills itself as the oldest American orchestra west of the Rockies, said it will cancel all of its November and December concerts and made no guarantees that the rest of its 2009-10 season would go on.

"We cannot spend money we do not have," said Majken Mechling, the symphony's executive director. "We cannot continue with business as usual."

The symphony is just the latest in a string of high-profile bankruptcies to hit the local economy.

Over the past 18 months, the state's largest phone company, Hawaiian Telcom Inc., local retailer Hilo Hattie and Hawaii Medical Center have filed for bankruptcy reorganization.

Mechling said the symphony has accumulated a debt of more than $1 million and has struggled in recent years to meet its $4.1 million-a-year payroll.

If the symphony resumes its 2009-10 season next year, it will be a scaled-down version. Mechling said the symphony plans to reduce its payroll expenses by half, which can be achieved through a combination of job cuts and fewer concerts.

In the worst case, up to half of the symphony's musicians could be laid off.

Mechling said that all but six of the symphony's 22 administrative staff have been laid off in recent days.

"What we do know is we have to reduce the payroll and the payroll has to be reduced substantially," she said.

The bankruptcy, which likely will be filed next week, caps a tumultuous two years for the symphony and its employees.

Musicians went several months this year without regular paychecks, resulting in high turnover.

The symphony's 84 full-time and part-time musicians later agreed to a 15 percent pay cut in September for the current season.

Steve Dinion, chairman of the musicians orchestra committee, said the musicians were devastated by yesterday's announcement.

Dinion, a timpanist in the symphony, said musicians have continued to perform for the symphony during the past two years despite going "months and months without paychecks."

He added that about half of the symphony's musicians were notified yesterday that their health insurance coverage would be terminated by HMSA.

"We're in shock that this is happening," Dinion said. "We think canceling concerts does a disservice to the community and ... the symphony's loyal subscribers."

Founded in 1900, the Honolulu Symphony is one of the largest performing arts organizations in Hawai'i.

Promotional material on its Web site boasts that it has endured "two World Wars, the Great Depression, financial crises, and changing musical and cultural fashions."

In past financial crises, the symphony has received last-minute donations from wealthy local business people, but during the current recession those gifts have been few.

Mechling said the symphony has not been economically sustainable for the past 10 years because of high operating costs. And while big donors in the past helped cover the costs, it wasn't always enough, she said.

"We've had angel donors that have come to the rescue but they've never totally rescued us," Mechling said. "They just put a Band-Aid on this big gaping hole and people perceive that it's being rescued."

The Honolulu Symphony joins a host of Mainland symphonies — including those in San Antonio, Nashville, Colorado Springs, San Diego and Oakland — that have filed for bankruptcy during the past two decades.

Some, like Oakland and San Diego, filed for bankruptcy liquidation but were resurrected years later thanks to an economic rebound and the largesse of wealthy benefactors.

Symphony officials said they have gotten a lot of calls in recent days when reports of a looming bankruptcy hit the news.

There have been few refund requests and donors have been supportive, Mechling said.

"The Honolulu Symphony Orchestra has achieved a legacy that is priceless and one that can be conceivably rekindled with the combined willingness of community, board and musicians," said Peter Shaindlin, the symphony's chairman.