Sea Summit at Marblehead, a new luxury development in San Clemente, Calif., will feature Spanish-style, seaside homes with prices up to $3 million. Its developers are targeting coastal homeowners and “move-down buyers” from affluent parts of Southern California, but they’re also aiming to attract one resident in particular: the California gnatcatcher. The developer, Taylor Morrison Home, acquired the rights to this 248-acre coastal plot last year, with the condition that 116 acres be set aside as a nature preserve. The company will spend $4 million to reinstall native vegetation that will attract species of birds like the gnatcatcher and to manage the habitat. The preserve is overseen by a nonprofit conservation group supported by an endowment established by the prior developer. Sea Summit is one of a growing number of high-end real-estate developments that have a large nature preserve as the primary draw. In some of these communities, homeowners pay a premium to live near a piece of shared, unspoiled nature—even though their own lots may be relatively puny. Marci and Shaun Skinner, 51 and 53 respectively, came to see the Sea Summit development site in July. Though there were no homes to tour—and they weren’t quite ready to sell their house in Rancho Cucamonga, Calif.—they signed a purchase agreement and put down a deposit on a $1.6 million house three days later. Their new home, which will be finished by year’s end, is just steps from the preserve, on a 6,250-square-foot lot.
“The fact that the land will be in preserve forever makes it feel much more open,” said Mr. Skinner, an executive for a commercial truck manufacturer who was turned off by how dense and urban most Southern California beach cities are. When Rob Brinson, an Atlanta-based photographer, was looking for a vacation home, he wanted to avoid places anchored by a golf course. Instead, he was looking for a community interested in nature and conservation, he said. His search led him to Serenbe, about 33 miles southwest of Atlanta, where he spent $1.3 million to build a 3,000-square-foot house. Mr. Brinson, 61, said the $400,000 he spent on his ½-acre lot within Serenbe might have purchased an entire farm outside of it. “But I have the best of both worlds,” with access to 700 acres of green space, Mr. Brinson said. “I love that I don’t have to do much yard maintenance.” Randall Arendt is a conservation planner in Brunswick, Maine who has helped design 38 conservation communities in the U.S. and Canada over the past 20 years. Much of his work has been convincing local governments to allow homes to be built more compactly so that developers can devote chunks of land they could have built on to green space, he said. He has also worked on convincing developers that they can make “even more money when conservation land forms a significant part of their community design,” he said. “It was harder in the past to sell developers on the idea that it could pay to not develop,” said Mr. Arendt. By contrast, today’s developers see nature preserves as relatively low-cost amenities that are highly valued by buyers, he said. Nature preserves are also replacing the amenity that used to serve as the hub for many luxury developments: the sprawling golf course. Golf courses’ popularity surged in the 1990s because “developers could charge 10% to 25% more over a non-golf development,” said Ed McMahon, a senior resident fellow at the Urban Land Institute. But with golf losing popularity, that trend has reversed: As of January, there were 15,372 golf courses in the U.S., down over 4% from 2005, according to the National Golf Foundation. More:'Eco-Serene' Is the Latest Miami Amenity Research has shown many people who buy homes on or near golf courses don’t even play the game, Mr. McMahon said; they just want to live near green space. Some nature preserves, such as the one at Sea Summit, are open to the public; many others, such as the one at Serenbe, are private land for the use of residents and their guests. Home buyers can usually only be sure that land is protected forever if it is held in a legal designation known as a conservation easement, in which either a government body or private land trust is empowered to constrain development on it, even if the land is sold to a new owner. If buyers want to be assured that the preserve will always be there, they should look up the deed and make sure that the deed protects the land in perpetuity, said Karin Gross, an IRS attorney specializing in charitable contribution deductions. “If you don’t have a conservation easement, that’s just set-aside land until the developer decides to build on it,” Mr. Arendt said. Easements have exploded: There were over 16 million acres of land held in local and state land trusts in 2010, compared with 5.5 million in 2000, according to the Land Trust Alliance, a Washington-based trade group. One reason for their popularity: Conservation easements can—though don't always—confer state and federal tax advantages. While conservation donations can reassure home buyers, they are not always problem-free. In Santa Fe, N.M., when developer Ralph Brutsche wanted to sell lots for 287 high-end homes in the northeast part of the city, he donated 300 acres of surrounding land to the Nature Conservancy. His purpose, said Mr. Brutsche, was “for the property surrounding the development to be free and open space for the comfort of the owners.” He was also seeking tax advantages which, he said, he didn't end up receiving. By 2010, Mr. Brutsche said he had sold 159 lots. Mr. Brutsche filed for chapter 11 bankruptcy in 2011. As part of bankruptcy proceedings, trustee Yvette J. Gonzales, a Santa Fe-based attorney, pursued a lawsuit against the Nature Conservancy, seeking to rescind part of the donation. The Canyon Neighborhood Association, representing about 650 neighbors, sprang into action. The Association worried that “instead of having this wildlife area and view, we would have some homes,” said director Richard Ellenberg. His group joined the lawsuit, arguing that the donation should not be rescinded, Mr. Ellenberg said. Mr. Brutsche said that it was never his intention to use the land for anything but a wildlife preserve. In late September, the judge ruled against the trustee, which means the donation will remain as is. Not all developers sacrifice land on which they could have built houses. In Darien, Conn., Kensett is a new community of townhouse condominiums on 15 acres, five of which are set aside as a nature preserve. Those 5 acres weren’t buildable to begin with, said developer Bill McGuinness of Sun Homes, based in Pawling, N.Y., because they are on protected watershed. Rather than fencing off the area, the company spent about $100,000 to “make it into an amenity,” building trails, removing invasive species and stocking a pond with native fish and frogs. So far, 55 of the total 62 homes have sold for $1.3 million to $2.2 million, Mr. McGuiness said. Some communities build activities and programming around their nature preserves. On Spring Island in South Carolina, Martha McMahon, 63, has taken the community’s 12-week “master naturalist” course, where she studied the flora and fauna in the preserve. She has also gone on kayaking trips and participated in the “Owl Prowl,” where neighbors listen for owls at night. Ms. McMahon and her husband, Bill McMahon, a retired banker, built a 4,000-square-foot house for about $2 million on Spring Island in 2007, drawn in part by its 1,200 acre nature preserve. “It’s spiritual and peaceful, and it puts us in touch with what is really important,” Ms. McMahon said. Write to Katy McLaughlin at katy.mclaughlin@wsj.com Corrections & Amplifications: Spring Island is in South Carolina. An earlier version of this article incorrectly stated that it is in Georgia. (11/5/2015) This article originally appeared in The Wall Street Journal.