The men gathered in a new golf clubhouse here a couple of weeks ago circled the problem from every angle, like caddies lining up a shot out of the rough.

“We have to change our mentality,” said Richard Rocchio, a public relations consultant.

“The problem is time,” offered Walter Hurney, a real estate developer. “There just isn’t enough time. Men won’t spend a whole day away from their family anymore.”

William A. Gatz, owner of the Long Island National Golf Club in Riverhead, said the problem was fundamental economics: too much supply, not enough demand.

The problem was not a game of golf. It was the game of golf itself.

Over the past decade, the leisure activity most closely associated with corporate success in America has been in a kind of recession.

The total number of people who play has declined or remained flat each year since 2000, dropping to about 26 million from 30 million, according to the National Golf Foundation and the Sporting Goods Manufacturers Association.

More troubling to golf boosters, the number of people who play 25 times a year or more fell to 4.6 million in 2005 from 6.9 million in 2000, a loss of about a third.

The industry now counts its core players as those who golf eight or more times a year. That number, too, has fallen, but more slowly: to 15 million in 2006 from 17.7 million in 2000, according to the National Golf Foundation.

The five men who met here at the Wind Watch Golf Club a couple of weeks ago, golf aficionados all, wondered out loud about the reasons. Was it the economy? Changing family dynamics? A glut of golf courses? A surfeit of etiquette rules — like not letting people use their cellphones for the four hours it typically takes to play a round of 18 holes?

Or was it just the four hours?

Here on Long Island, where there are more than 100 private courses, golf course owners have tried various strategies: coupons and trial memberships, aggressive marketing for corporate and charity tournaments, and even some forays into the wedding business.

Over coffee with a representative of the National Golf Course Owners Association, the owners of four golf courses discussed forming an owners’ cooperative to market golf on Long Island and, perhaps, to purchase staples like golf carts and fertilizer more cheaply.

They strategized about marketing to women, who make up about 25 percent of golfers nationally; recruiting young players with a high school tournament; attracting families with special rates; realigning courses to 6-hole rounds, instead of 9 or 18; and seeking tax breaks, on the premise that golf courses, even private ones, provide publicly beneficial open space.

“When the ship is sinking, it’s time to get creative,” said Mr. Hurney, a principal owner of the Great Rock Golf Club in Wading River, which last summer erected a 4,000-square-foot tent for social events, including weddings, christenings and communions.

The disappearance of golfers over the past several years is part of a broader decline in outdoor activities — including tennis, swimming, hiking, biking and downhill skiing — according to a number of academic and recreation industry studies.

A 2006 study by the United States Tennis Association, which has battled the trend somewhat successfully with a forceful campaign to recruit young players, found that punishing hurricane seasons factored into the decline of play in the South, while the soaring popularity of electronic games and newer sports like skateboarding was diminishing the number of new tennis players everywhere.

Rodney B. Warnick, a professor of recreation studies and tourism at the University of Massachusetts, said that the aging population of the United States was probably a part of the problem, too, and that “there is a younger generation that is just not as active.”

But golf, a sport of long-term investors — both those who buy the expensive equipment and those who build the princely estates on which it is played — has always seemed to exist in a world above the fray of shifting demographics. Not anymore.

Jim Kass, the research director of the National Golf Foundation, an industry group, said the gradual but prolonged slump in golf has defied the adage, “Once a golfer, always a golfer.” About three million golfers quit playing each year, and slightly fewer than that have been picking it up. A two-year campaign by the foundation to bring new players into the game, he said, “hasn’t shown much in the way of results.”

“The man in the street will tell you that golf is booming because he sees Tiger Woods on TV,” Mr. Kass said. “But we track the reality. The reality is, while we haven’t exactly tanked, the numbers have been disappointing for some time.”

Surveys sponsored by the foundation have asked players what keeps them away. “The answer is usually economic,” Mr. Kass said. “No time. Two jobs. Real wages not going up. Pensions going away. Corporate cutbacks in country club memberships — all that doom and gloom stuff.”

In many parts of the country, high expectations for a golf bonanza paralleling baby boomer retirements led to what is now considered a vast overbuilding of golf courses.

Between 1990 and 2003, developers built more than 3,000 new golf courses in the United States, bringing the total to about 16,000. Several hundred have closed in the last few years, most of them in Arizona, Florida, Michigan and South Carolina, according to the foundation.

(Scores more courses are listed for sale on the Web site of the National Golf Course Owners Association, which lists, for example, a North Carolina property described as “two 18-hole championship courses, great mountain locations, profitable, $1.5 million revenues, Bermuda fairways, bent grass, nice clubhouses, one at $5.5 million, other at $2.5 million — possible some owner financing.”)

At the meeting here, there was a consensus that changing family dynamics have had a profound effect on the sport.

“Years ago, men thought nothing of spending the whole day playing golf — maybe Saturday and Sunday both,” said Mr. Rocchio, the public relations consultant, who is also the New York regional director of the National Golf Course Owners Association. “Today, he is driving his kids to their soccer games. Maybe he’s playing a round early in the morning. But he has to get back home in time for lunch.”

Mr. Hurney, the real estate developer, chimed in, “Which is why if we don’t repackage our facilities to a more family orientation, we’re dead.”

To help keep the Great Rock Golf Club afloat, owners erected their large climate-controlled tent near the 18th green last summer. It sat next to the restaurant, Blackwell’s, already operating there. By most accounts, it has been a boon to the club — though perhaps not a hole in one.

Residents of the surrounding neighborhood have complained about party noise, and last year more than 40 signed a petition asking the town of Riverhead to intervene. Town officials are reviewing whether the tent meets local zoning regulations, but have not issued any noise summonses. Mr. Hurney told them he had purchased a decibel meter and would try to hire quieter entertainment.

One neighbor, Dominique Mendez, whose home is about 600 feet from the 18th hole, said, “We bought our house here because we wanted to live in a quiet place, and we thought a golf course would be nice to see from the window. Instead, people have to turn up their air conditioners or wear earplugs at night because of the music thumping.”

During weddings, she said: “you can hear the D.J., ‘We’re gonna do the garter!’ It’s a little much.”