By Sue Pierce, Halogen Guides

updated 5:30 p.m. ET July 25, 2008

A 400-foot ship enters a harbor ...

The beginning of a joke? Not exactly, but it does pose an interesting question for the yachting industry: Then what happens? As the number of megayachts on the seas continues to grow, only a limited number of marinas can accommodate these giants, and competition for slips is fierce.

There are more 2,000 megayachts in the world, and that number is growing. Since 1997, the number of megayachts built has increased 400 percent. While the definition of a megayacht starts with a length of 80 feet, those that stretch more than 200 feet constitute the most rapid sales growth.

Megayacht captains struggle to find marinas that not only have adequate dock space, but the facilities—like speedy gas pumps—needed to berth these oversized vessels. Refueling a megayacht isn’t as simple as pulling up to a Mobile. The 414-foot Octopus, owned by Microsoft co-founder Paul Allen, holds nearly 225,000 gallons of fuel and can take anywhere from eight to 24 hours to refuel, depending on a marina’s pump capacity. Provisioning for these yachts can be another challenge for smaller marinas, which may not be able to provide requested items like grass-fed filet mignon or a particular bottle of white burgundy.

As a result, an entire new sector in the yachting industry is booming. “Marinas on the whole are upgrading their services,” explains Chuck Smith of Island Global Yachting (IGY), a Florida-based company that owns, develops and manages luxury marinas around the world. “The marina industry is in transition because vessels have gotten bigger.”

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Island Global Yachting jumped on the opportunity to create marinas tailored especially for megayachts, with the size and facilities to host the actual vessels, as well as an adjacent marina village designed to be a desirable destination for both guests and crew.

When IGY opened Yacht Haven Grande on St. Thomas in 2006, it was the first marina of its kind. It featured 48 slips that could accommodate yachts larger than 450-feet, and guests could step off their yachts and stroll through luxury shops like Louis Vuitton and Gucci. The marina quickly became a destination for the most mega of megayachts. In fact, the 453-foot Rising Sun, owned by Oracle founder Larry Ellison, had never pulled into a dock space until she visited Yacht Haven Grande.

To woo the growing megayacht crowd, some marinas are beginning to offer the same kind of services provided by a five-star resort, such as 24-hour concierge assistance and customized food requests. These marinas give guests the opportunity to have or do whatever they want, whenever they want it. “The concierge at Yacht Haven Grande has provided nannies for charter guests,” says Smith. “One time they delivered $10,000 worth of bottled water to a yacht.”

FIG Luxury Living, LLC Today there are no large marinas for megayachts in the U.S., but that's about to change. The Island Gardens development on Watson Island in Miami's Biscayne Bay will have 50 slips specifically designed for megayachts, each angled to capture unobstructed views of downtown Miami. Also part of the $480 million development are two luxury hotels, fractional residences and of course, spas, restaurants and shops.

And there is more in store for demanding megayacht owners. By 2010, several marinas will be opening their docks to megayachts and well-designed marina villages to the guests onboard. While the Mediterranean holds the title of most popular destination, marina developers are looking to markets like St. Lucia, Croatia and Greece for more space. In Dubai, developers are literally creating new coastline with hundreds of man-made islands. IGY has been commissioned to build every marina in these new developments, resulting in 40,000 new slips and a marina dedicated exclusively to megayachts.

But even with the development of the largest marinas yet, the growing popularity of these mammoth vessels will keep demand for slips high. Today, the biggest megayacht marinas are booked well in advance. New marinas, with more elbow room and even more luxury services, are also expected to fill up fast. So when that 400-foot yacht enters the harbor, she had better have a reservation.

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