Not too long ago, the wait list to get into some of the region’s most popular marinas could be years long.

But increasing numbers of boats have vacated as the recession deepened, leaving marinas around Puget Sound struggling to fill empty slips, especially in smaller sizes. Some are now offering deals and promotions in an effort to attract new tenants.

The Port of Edmonds, for example, launched a “2010 boat show special,” offering new tenants first and last month’s rent for $20.10 if they sign up by March 1 and allowing them to use credit cards for waiting list applications (in the past, only cash or checks were accepted).

Marla Kempf, the port’s deputy director, said the marina has twice as many vacancies as usual for slips under 30 feet and dry storage occupancy is also down. The number of names on the marina’s waiting list, she said, has dropped from 205 five years ago to around 80.

“There’s a huge decrease in the trend of the waiting list going down,” she said. “We want people to know that if they used to think they can’t get into Edmonds, now might be the time to get on the waiting list.”

The situation is similar at the Port of Everett Marina, which has an occupancy rate of about 75 percent and vacancies primarily in slips of 32 feet and less. The marina is offering a special that started Jan. 29, the first day of the Seattle Boat Show, and runs until Feb. 15. New tenants get the first month of moorage for $1 if they sign up for six months, and existing tenants can get a month of moorage for a buck by referring a new tenant.

“We’re hoping that by offering this special, we may be able to generate a little more year-round interest,” said Cyndy Olson, the Port of Everett’s marina director.

That hope is shared by Paul Stannert, harbormaster for the La Conner Marina. The marina’s occupancy rate is at about 75 percent, following a decline after liveaboards were eliminated in 2007. Stannert said he’s hoping to fill some of the vacancies, many of them in slips 30 feet and under, by offering new tenants three free months of moorage if they sign up by Feb. 12.

“We’ve been very aggressive with our marketing,” he said.

The rise in vacancies begs an obvious question: where are all the boats going? Traditionally, trailerable boats are often moved from marinas during the off-season to less expensive drydock facilities or stored on private property. While the seasonal fluctuation in smaller slips is nothing new, marina operators say it has become increasingly pronounced since the economic downturn.

“During off-peak season, people say, ‘Why do I want to spend money keeping my boat in the water during the winter time?’” Kempf said. “People are just being more cautious with their money and their discretionary income.”

Additionally, as boats have increased in size, older facilities such as the Port of Everett Marina, built in 1965, have seen demand for larger slips increase and smaller slips become harder to fill.

“Boats have gotten bigger, and the demand has shifted to larger size slips,” Olson sad. “It’s that size range of 36 feet and under where we’re seeing a lot of vacancies. It’s a commonality that we have (with other marinas) to one extent or another.”

An exception is Shilshole Bay Marina, which in recent years underwent an $80 million renovation that included adding more larger slips. Now, its employees sit in an attractive new marina building overlooking an empty space where a new Anthony’s restaurant was scheduled for development, and beyond that, a sizeable number of large, empty slips.

The Port of Seattle ran a promotion during the Seattle Boat Show in an effort to fill some of those spots, offering new tenants a first month of moorage for $1 if they sign up for six months . Megan Deinas, the Port of Seattle’s marketing manager for harbor services, said the marina has a vacancy rate of about seven percent, with most empty slips ranging from 38 feet to 100 feet.

“We have quite a few vacancies that we’re not used to seeing,” she said, “so we felt we needed to do something that would spark interest and remind people that Shilshole’s there and it’s a great facility.”

Other moorage specials currently on around the region include the following:

The Port of Bremerton Marina has three “boat show specials” on through March 31. Boaters who stay for six months and pay on a month-to-month basis get the seventh month for $1, plus $100 of fuel vouchers redeemable at the Port Orchard Marina fuel dock. Paying for six months up front gets you $200 worth of fuel vouchers and two months of moorage for $2. If you pre-pay for a year, you’ll get $300 in fuel vouchers and moorage for months 13 through 17 at $1 a month.

Foss Harbor Marina in Tacoma is offering new tenants five percent off moorage fees if they pay for six months in advance and 10 percent off if they pay for a year. Military members get a 20 percent discount on moorage (offer tentatively scheduled to expire in April) and existing tenants get 20 percent off the next month’s moorage for referring a new tenant.

Westport Marina, in Grays Harbor County, is offering three months of moorage for $420 for boats 29 feet and under, plus a free launch pass good from Jan. 1 through Dec. 31. Fees must be paid in advance.