Some transportation companies in the tourism industry say they have been able to pass on higher gas and diesel fuel costs to customers. Others, citing set tour packages and bureaucratic procedures, say they've absorbed much of the costs.

Higher fuel prices have had an "adverse impact" on Roberts Hawaii, the largest privately-owned tour and transportation company in Hawai'i, said president Troy Iwamoto.

"Each one cent fuel increase costs our bottom line $20,000, and these are unrecoverable impacts, so imagine the full effect these very volatile months have had on our business operating costs," he said. "Our visitor industry tour packages and programs have already been created, marketed, advertised and sold at the old 2005 price through wholesaler, activity and attractions desks or directly, so we cannot pass on the increased expenses."

He said the company can eventually increase charter rates, but because they must be approved by the state Public Utilities Commission, "we are typically chasing our ever increasing cost structure as we wait for approvals."

Roberts Hawaii has raised its rates three times between January 2004 and February 2005 based on operating expenses, including fuel, said spokeswoman Sam Shenkus. The increases raised the $25 adult rate for a tour that includes the Arizona Memorial and Pearl Harbor to $27.08.

The commission is in its second year of a "zone of reasonableness" program that expedites the review and approval process for rate changes within plus or minus 10 percent of a motor carrier's base rate. Fuel surcharges have recently been included in that range.

Roberts Hawaii is taking steps to reduce costs, including upgrading its fleet of over 1,000 vehicles with more fuel-efficient equipment, Iwamoto said.

Average diesel fuel prices in Hawai'i were $2.75 a gallon, up from $2.18 a year ago, according to yesterday's AAA Daily Fuel Gauge Report. The average price of regular gasoline was $2.52 a gallon, compared to $2.15 a year ago.

"It's another challenge in the world of business," said Steven Kolt, managing director of V.I.P. Transportation, whose primary business includes shuttles to the airport, the Arizona Memorial and the Aloha Stadium swap meet as well as charters.

"There's always a time lag between any increased cost and when we can get approval to raise the rate, and so that hurts us," he said. "And then we can't go retroactive; it's not fair to our customers."

Kolt said the company, which has a fleet of 67 motor coaches, mini-buses and other vehicles, may offer incentives to drivers who use no more than a certain amount of fuel on certain routes and is implementing a computer program to monitor the fuel consumed by each vehicle compared to the number of miles.

"The rising cost of crude has a very negative effect on our industry," said Gareth Sakakida, managing director of the Hawaii Transportation Association. "It's a very substantial factor in operating costs."

"The cost of crude not only impacts us in the cost of fuel, but the cost of our vehicles. Many components or features in the vehicles are plastics, and plastics use the same raw material as fuel. The cost of those things go up and that adds to our operating costs."

For Polynesian Adventure Tours, which has 130 buses and other vehicles in its fleet, rising fuel costs "have had an impact but at this time we have not had to raise costs to our consumers," said a company spokesperson.

Polynesian Hospitality, which mainly provides charter tours and shuttle service between the airport and hotels for corporate and incentive groups, has increased its rates three times since January 2004, said secretary/treasurer Lawson Teshima. The average price of a shuttle trip from the hotels to the airport has gone from $8 to $9.

The price of diesel fuel has gone up about 45 percent since last year, he said.

"It's increased our operating (costs) of course, but in the same light we've had to ask for increases in our rates," he said. "So we're affected, but we've been able to pass our costs on."