Ski resorts in Vermont, New Hampshire and Maine are looking for more gray on the slopes. As a growing number of baby boomers approach retirement age, developers are breaking ground on houses and condominiums in an effort to keep them and their money on the East Coast.

Stowe Mountain Resort in Vermont, owned by American International Group Inc., the world's largest insurer, sold 14 home lots earlier this year at an average $1.1 million apiece, said Gary Gosztonyi, 54, director of sales. Vermont's Killington Resort, the Northeast's biggest ski resort, plans to build a village next year with lots priced as high as $5 million.

New England ski resorts are trying to ignite the interest of baby boomers, who boosted sales of second homes last year by 16 percent, according to a March report by the National Association of Realtors. More than 17 million people will turn 60 over the next five years, as the first wave of those born from 1946 to 1964 enters retirement, according to the 2000 U.S. Census.

"The demographics are favorable for us," said Michael Berry, president of the National Ski Areas Association in Lakewood, Colo. "We're resonating with the baby-boom generation. They're more active, the equipment has improved and the amenities are better."

Persuading skiers to choose the Northeast over the Rocky Mountains has proved an uphill battle. Last year, about 13.7 million skiers visited resorts in the northeastern United States, 30 percent fewer than the 19.6 million who favored the slopes out West, according to the National Ski Areas Association, an industry trade group.

Older skiers may be easier to sell on the virtues of the Northeast. Baby boomers already account for 30 percent to 31 percent of the populations of Vermont, New Hampshire and Maine, the highest proportions in the United States outside of Alaska, according to the 2000 census data.

Keeping them in-state when they retire, and attracting newcomers with money and leisure time to spare, may give ski areas an opportunity to diversify sources of revenue beyond lift tickets and ski lessons.

The push to sell vacation property comes as rising interest rates are beginning to cut sales of primary residences. Sales of new and existing homes are projected to fall 3.4 percent to 8.01 million in 2006 from a record 8.29 million this year, according to the Washington-based Mortgage Bankers Association.

There also is concern that condominium buyers will use their properties only a few times a year, reducing the opportunity for revenue from summer activities including golf and hiking. Finding ways to generate income during the warmer seasons has become important as global warming makes winters less predictable, said Nolan Rosall, 60, president of RRC Associates, a ski resort planning firm in Boulder, Colo.

"They can't assume that success in the past automatically means success in the future," he said.

Resorts in the Rocky Mountains also are making similar development efforts. Vail Resorts Inc., which owns resorts in Colorado and Wyoming, is spending $500 million on its "New Dawn" project, which includes plans for condominiums and homes.

Vail Resorts said its net loss for the quarter ended Oct. 31 widened by 9.1 percent to $34.3 million, or 93 cents a share, as lodging and real-estate revenue declined. The Vail, Colo., company forecast net income will rise as much as 69 percent to $39 million in the year that ends July 31.

Stowe is investing $400 million in the Spruce Peak at Stowe community, which will add more than 400 homes and amenities such as a performing arts center. The resort is run by Mt. Mansfield Co., an AIG subsidiary.

Residents will be able to join the new "Stowe Mountain Club," which will offer services such as valet parking, concierge and entry to the resort's golf course, according to its Web site.

While the official opening isn't until 2007, about 85 percent of more than 150 planned condominiums have been sold. Stowe also has sold 14 of 17 Spruce Peak mountain cabins for about $2 million each.

Killington, owned by Park City, Utah-based American Skiing Co., plans to build a village with 1,400 to 1,800 condominiums and single-family lots, spokesman Tom Horrocks said.

Vancouver-based Intrawest Corp.'s Stratton Mountain Resort in Vermont is completing construction at its TreeTop site, which offers luxury apartments and Adirondack-style cabins on the mountain that sell for more than $1 million.

Sugarbush Resort in Warren, Vt., in August began construction on a 61-unit luxury apartment complex with condominiums priced as high as $1.2 million. Sugarbush is owned by closely held Summit Ventures LLC.

One-third of the condominiums at Sugarbush's planned Clay Brook site have been sold for year-round use and another quarter have been sold to multiple owners as timeshares. The resort, which plans to spend $45 million revamping its village and building Clay Brook, expects the complex to open next year.

David Dillon, 57, president of the Vermont Ski Area Association in Montpelier, said resorts in New England are trying to prevent oversupply by selling homes before they're constructed. To him, the risks of not offering luxury amenities and properties that attract wealthy vacationers are greater.

"If you want people to visit your resort, it's necessary," Dillon said.

As baby boomers approach retirement age, New England resort developers are building luxury homes to keep them from defecting to ski spots in the Rockies.A waiter serves restaurant patrons at Stowe Mountain Resort in Stowe, Vt. The resort is owned by insurer American International Group Inc.