CODY - Advance reservations by tourists planning to visit the greater Yellowstone region this summer are below last year's levels, but industry leaders say they are optimistic that strong last-minute bookings will bolster the season.

A weak national economy may force some travelers to cancel or curtail their vacations, but lower gas prices could lure others to drive to national parks and other attractions in Wyoming and Montana.

The most recent projection from the Department of Energy is that regular-grade gasoline prices will remain at about $2 a gallon this year, while diesel should cost about $2.19, although summer price spikes are possible.

Planners at the Buffalo Bill Historical Center in Cody are anticipating flat visitor numbers this year, with a slight rise possible in recreational vehicle traffic compared with last year, when RV numbers had dipped by as much as one-third during some months.

"Flat is the new up," said museum spokesman Lee Haines, explaining that matching last year's visitor numbers would be a welcome accomplishment in the down economy.

Haines said many RV owners are retired, and therefore have more flexible travel schedules, allowing them to drive when gas prices are lower.

But those same people have suffered heavy losses in their retirement savings, and may spend less as a result, he said.

Jim Pricco, owner of a large wholesale bakery in Los Angeles, said that low gas prices have persuaded him to plan a return RV trip to Yellowstone National Park.

"Compared to last year, gas is cheap, so we're going to go up through Oregon and then come over into Yellowstone from that way," he said.

But Pricco said a battered stock market means a tighter overall vacation budget for his family and friends.

"The economy last year nearly killed us. Gas tripled and they couldn't raise wheat prices quick enough. It was ugly. I had retired, and ended up having to go back to work. We laid off everybody we could," he said.

"There's a sense of uncertainty about the year" among some Cody retailers, Haines said, adding that the museum is making "subtle changes" in its main entrance and exit to help route foot traffic into the gift shop.

Attendees at Montana's annual travel conference, held earlier this week in Helena, were also uncertain about the season and reported weak spring bookings, said Sarah Lawlor, spokeswoman for Travel Montana, the state's tourism office.

Though July and August look strong, reservations for earlier months are down, and the state's travel research office is for the first time predicting a 2 percent drop from the year before, she said.

The weak economy is likely to push travelers to shop for bargains and book later, but it could also mean more repeat visitors to Montana, Lawlor said.

"Montana has a high return rate and high visitor satisfaction, so there are a lot of repeat visitor bookings in a trend we call 'tried-and-true travel."' she said.

Lawlor said the state is focusing its marketing on places such as Minneapolis and Seattle, from which many visitors travel by car.

Advance reservations so far this year are down 13 percent from last year, said Rick Hoeninghausen, director of sales and marketing for Xanterra Parks and Resorts, the main lodging company in Yellowstone.

Though bookings are good for July and August, when rooms are typically sold out, group tours and early season stays are down, he said.

"I can't say it was totally unexpected," Hoeninghausen said, adding that "this is a new economic situation that is not like anything most of us here now can remember."

He said Xanterra is offering discounts through mid-June on vacation packages that include tours and other activities, in an attempt to entice travelers to come to Yellowstone before the busiest part of summer.

"Dude ranch reservations as a whole are down on average throughout the association by about 15 percent," said Colleen Hodson, director of the Dude Ranchers' Association in Cody.

Hodson said member ranches in Arizona, where the travel season starts earlier, are reporting some cancellations, but "they are now running about 10 percent down from last year."

Bookings for large groups such as family reunions are down sharply, she said, adding that many visitors are opting to come later in the season, when rates are lower.

"People are bargain-shopping, and there are some great bargains out there. Unfortunately, ranchers' fixed costs don't change. The horses don't eat less because the economy is off. But we're holding out high hopes for last-minute bookings," she said.

"We've been doing this since 1926, and dude ranchers are resilient. You can't keep us down," Hodson said.