As the world’s population grows, so does demand for land. Agriculture, livestock, housing, and other human infrastructure have claimed half of the Earth’s habitable land. One upshot of land’s scarcity is that setting aside big tracts to protect imperiled species and carbon-rich forests is increasingly expensive.

Enter the Airbnb business model. While it’s not a panacea, it provides an attractive solution—not just for housing but also for conservation in environments as different as North America and Africa.

Much as homeowners and long-term renters can use Airbnb and similar services to turn their living space into pop-up hotels when demand warrants it, conservationists are creating “pop-up nature reserves” on private land during times of the year when the owner has less need for it. Farmers and conservationists take turns using the same parcel of land, turning an “either-or” into “both.” This model, moreover, allows the timing and placement of nature reserves to adapt dynamically as the climate, land use, and species’ needs change.

Consider how Airbnb works. Think of Tampa, Florida, during next February’s Super Bowl, when hotel rooms will be scarce and locals will be enticed to rent their homes to football fans. Something like that happens in the environmental realm, too: there is a surge in demand for protected land when migratory birds are passing through an area or a threatened species is breeding.

In the United States, The Nature Conservancy has been a pioneer in bringing the “sharing economy” business model to conservation. It has been temporarily expanding wetlands for migratory birds in California’s Sacramento Valley since 2014. In early fall, when shorebirds head south for the winter along the Pacific Flyway (which extends from Alaska to Patagonia), and again in late winter and early spring on their return journey, the birds need more wetlands than the remaining mix of parks and nature preserves provides.

A cornerstone of The Nature Conservancy’s strategy in the United States has been to acquire land and convert it into private reserves. However, this approach is expensive in California’s fertile Central Valley. Then came a big insight: “We could use a rent rather than buy model,” said Mark Reynolds, an ecologist with the nonprofit. He co-created a program named BirdReturns, based on this insight. The program pays rice farmers to flood their fields for a few crucial weeks each fall and spring.

Rice growers in the Sacramento Valley traditionally flood their fields to decompose crop residue after the September harvest each year. Even business-as-usual rice-growing offers habitat to migrating birds. But it would be quite a coincidence if the birds’ and the farmers’ calendars and needs were exactly aligned. They are not. For example, farmers keep 15 to 25 centimeters of standing water on their fields, which is too deep for many shorebirds.

Farmers usually draw down the water from their fields around February, to give the soil enough time to dry out before planting. But migratory birds heading north continue to pass through the Sacramento Valley from March to early May, depending on the species.

Thus, BirdReturns pays farmers to keep water on their fields into early spring, longer than they otherwise would. While keeping the fields flooded into May is too much risk for most farmers to take on (fields that are moist at planting time produce less rice), some of them are willing, for a price, to keep water on their fields later than usual—into, say, April—and at the shallower depth that suits shorebirds. The program strikes a similar deal with farmers in the fall. Shortly after harvest, some of them agree to flood their fields for the birds heading south.

And, by all accounts, BirdReturns pop-up wetlands are working. The density of shorebirds was five times as high on the fields flooded through the program as on nearby fields, for example, according to a study by Dr. Reynolds and his colleagues published in Science Advances that analyzed the 2014 season.

Greg Golet, one of the authors of that study and an ecologist at The Nature Conservancy, told me that the team has tweaked the program over the years, based on what the field observations have revealed and on feedback from the farmers. In the initial year, the contract specified that the soil should be fairly smooth—free of large clods of dirt that break the surface of the water. But after noticing that fields with more dirt clods actually attracted more birds, they removed that counterproductive rule. The program is also now more concentrated on early fall and late spring, when their modeling and data analysis have shown that, without pop-up wetlands, surface water is particularly scarce.

Dr. Golet told me this last October, while showing me one of the enrolled fields in the town of Colusa, about 100 kilometers northwest of Sacramento. The season when southbound birds pass through the valley was winding down, but the fields were still full of dunlins, sandpipers, and other shorebirds. He also shared some of the new directions for the work. A big focus is designing programs that create multiple conservation benefits. The team is working with landowners who are flooding their fields with surface water to recharge groundwater stores—and is seeing whether, with some adjustments in timing, location, and water levels, those efforts can create more bird habitat too.

A powerful feature of the Airbnb model is that it is dynamic. It would not make sense for Tampa to build a bunch of new hotels to satisfy next year’s short-lived influx of Super Bowl visitors. A visitor entering into a long-term lease would similarly be inefficient. Instead, she can rent a place in Tampa for the few days around February 7, 2021, when she needs it. During those exceptional few days, the usual residents of that house or apartment do not value their home as much as the visitor does. Something similar can happen around February 6, 2022, in Los Angeles, the site of that year’s Super Bowl. Airbnb rentals create supply to match temporary spikes in demand, wherever and whenever they occur.

The need for extra wetlands is also dynamic. The exact timing and path of birds’ migration vary each year, and the program can adjust where and when it rents land. How much land to enroll also depends on how much surface water there is. The early years of the program occurred during California’s prolonged drought, but when abundant rainfall returned in 2017, BirdReturns could dial back the amount of pop-up wetland it procured that year. Climate change might alter the capacity of natural wetlands as well as when and where birds migrate, increasing the importance of a fluid approach.

Dynamic conservation has long been in marine ecologists’ toolkit. Marine animals are always on the move, and no-fishing zones need to be nimble too. Since 2003, for example, scientists have combined sophisticated modeling and real-time satellite data to predict exactly where southern bluefish tuna are to be found off the coast of eastern Australia. The predictions guide where temporary fishing restrictions are put into place. Another example uses crowdsourced data from fishermen. The eCatch phone app, also created by The Nature Conservancy, allows fishermen to log where they have been catching high volumes of low-quota fish. The data help their peers steer clear of those hotspots and avoid a fishery closure triggered by overfishing.

As at sea, dynamic conservation on land is made possible by better and faster data. The BirdReturns team uses satellite imagery to assess surface water, which informs where pop-up wetlands are most needed. The team also predicts migratory paths using crowdsourced data from amateur bird-watchers, collected through the eBird app developed at Cornell University.

New data sources and modeling techniques lower program costs and enable greater scale. The team has experimented with acoustic monitoring and time-lapse photography to track the bird population, as a complement to the crowdsourced human sightings. They are also exploring whether they can replace in-person compliance checks of farmers with automated monitoring that applies machine-learning methods to high-resolution satellite imagery.

While technological advances are making dynamic conservation more powerful, climate change is making it more valuable. Nimbleness is a useful feature in the face of our increasingly volatile weather, but it even helps us adapt to wholly predictable trends. For example, The Nature Conservancy has deployed its pop-up habitat model to help sandhill cranes transition to a migration route that is more resilient to climate change and to society’s expanding footprint. They placed temporary wetlands somewhat inland from the cranes’ usual roosting ground in the Sacramento–San Joaquin Delta. The long-term vision is to coax the cranes toward new roosting spots that are less likely to be destroyed by sea-level rise and land-use changes. “You can really help those species by tracking the [landscape] changes and trying to put habitat where they are going to need it in future scenarios,” Dr. Reynolds said.

Unlike Airbnb rentals, there is no website to browse to find the going rate for renting rice fields. The BirdReturns answer to this problem was to set up a reverse auction. In a standard auction, the seller of a good or service (such as a piece of artwork, a closeout television, or a round of golf) solicits bids from potential buyers. In a reverse auction, the buyer solicits bids from potential sellers.

In this case, The Nature Conservancy is the buyer, and rice farmers in the Sacramento Valley are the sellers. Interested farmers submit bids that specify the minimum payment they would need to keep water on their fields for a specified window.

Eric Hallstein, an economist at The Nature Conservancy, was part of the team that created BirdReturns, along with Dr. Reynolds and their colleague, Sandi Matsumoto. He remembers the excitement of hitting upon the rent-don’t-buy idea, but “we had no idea what rent we should pay,” he added.

As luck would have it, Dr. Hallstein’s previous work as a management consultant had sent him to Detroit to help set up a reverse-auction platform for automobile parts. Years later, in what he called “one of those funny ways that life converges,” that experience helped him realize that the same tool was ideal for pricing pop-up wetlands.

An auction automatically adjusts the payment levels to match farmers’ costs. For example, flooding during the end of the spring migration season is trickier to fit into an annual rice-growing schedule than earlier in the season, so farmers’ bids—and hence the payments they receive—are higher. In addition, some farmers might ask for a higher price than others, because they are risk-averse about their fields drying in time or they face higher costs to access water.

Once the BirdReturns team has the bids, which farmers submit in private, they can accept the lowest bids or, more precisely, the ones that provide the most conservation per dollar, factoring in where habitat is especially needed. This way, their budget stretches further than if they offered a higher payment based on guessing what farmers needed to be paid. They also avoid setting such a low price that they attract few takers.

There is an entire branch of economics focused on the theory of auction design. Whether to pay a winner the amount she bid or pay all winners the highest accepted bid is just one of the many choices facing the auction designer. Another is what information, if any, to share with bidders about other bids. The theoretically “optimal” auction often embeds subtle features and extra rules to make it more difficult to game. In uncharted territory and unsure how complex to make the auction, Dr. Hallstein ran mock auctions in his office, asking his colleagues to bid for silly prizes. That convinced him to go with something pretty simple. “The bells and whistles just frustrated people,” he said. To his delight, when he ran the auction for real, the rice farmers took to it.

One of BirdReturns’s strengths is that it transforms an all-or-nothing approach to land use—either devoting it solely to private development or turning it into a nature reserve—into something in between. This idea has applications well beyond pop-up wetlands.

Take forest conservation. My own recent research, conducted with fellow economists as well as with ecologists, has focused on a program in western Uganda that offered payments to farmers if they refrained from cutting down primary forest that they owned. The program, run by a Ugandan nonprofit, turned out to be a remarkably inexpensive way to protect forests and thereby reduce carbon emissions, as reported in Science in 2017. For every $100 spent on the program, an extra acre of forest remained intact and 250 metric tons of carbon dioxide were kept out of the atmosphere. That benefit is worth $250 conservatively, and likely closer to $1500, based on the “social cost of carbon”—the estimated damage averted when we reduce carbon emissions. That’s a great return on a $100 investment, better than we get from many other efforts to mitigate climate change.

Through this program, the Ugandan farmers continued to own the land, live on it, and grow crops in already-cleared areas. In essence, the conservation organization rented the trees from the landowner, while the owner held on to other land-use rights. With BirdReturns pop-up reserves, the private and conservation uses of the land take turns. In this case, they happen simultaneously, by dividing up property rights in a more nuanced way than is typical: you get the rights to the trees; I get everything else.

Buying up the forest outright and turning it into traditional reserves not only would have cost more money but would have displaced thousands of people from their homes. Thus, the double-duty approach can also be more pro-poor and just.

Offering payment in exchange for conservation efforts and letting people choose whether to participate has advantages over banning deforestation. In the Ugandan setting, people often chop down and sell trees to pay hospital bills and school fees. A ban on harvesting would deprive very poor people of much-needed income. A landowner takes part in a voluntary program like this one only if he thinks the payment from the program outweighs what he is forgoing. If participation would make him poorer, he can simply decline the offer.

Moreover, a market-based approach can balance conservation goals with critical needs such as growing food. If a certain landowner is fantastic at farming—producing a lot of food for the community—it could very well make sense for her to continue to farm her land, even if doing so means clearing some forest.

At any given payment level, less-productive farmers will be more likely to take part in the program because the food production—and profit—they sacrifice by keeping their forest intact is small. That’s why proper pricing is important. If you offer an appropriate payment for conservation, the best farmers will decline it because they can earn more by expanding their farms, while the mediocre ones will sign up.

The Ugandan program paid a farmer 70,000 shillings (about $28 at the time) a year for each hectare of primary forest kept intact. The payment level was set by guesstimating how much income the typical farmer would have to forgo to conserve, and how much society values protecting the forest.

Our pilot program did not have a target amount of forest area we wanted to enroll, but if it had, the payment level might have ended up too high or too low to hit it.

A reverse auction would have reduced this risk. Auctions have been deployed with success in forest-conservation efforts. Economist Kelsey Jack piloted a program in Malawi that paid landowners to plant trees. Those interested submitted bids, indicating the lowest payment at which they would be willing to participate. Then the program selected the lowest bids, up to the point where its fixed budget was exhausted. Dr. Jack’s project compared the auction mechanism to just setting a price at the outset without soliciting bids. Her research determined that the auction produced more conservation per dollar spent.

The pioneer in conservation auctions is the BushTender program administered by the government of Victoria, Australia. Since 2001, the program has used auctions to set the price it pays private landowners for maintaining native vegetation. Good ideas tend to diffuse locally, so it is perhaps not surprising that Australia employs several other innovative uses. For example, the federal government pays sugar cane farmers to reduce nitrogen runoff into the Great Barrier Reef by adjusting their fertilizer use. It uses auctions to make that program as cost-effective as possible.

In a world upended by climate change and in which the human footprint is ever expanding, there are surely many more settings where auctions could be used. Doing so in various combinations with other elements of the Airbnb model—adaptability, real-time data, and land doing double duty—would help us accomplish more with limited conservation budgets.

Dynamic conservation doesn’t replace dedicated nature reserves and other static solutions, but it does extend our options. And one need only look around to realize that we need more innovation, more coexistence—and, above all, more options. Anything else in our rapidly changing world would be flat-footed.

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Seema Jayachandran is a professor of economics at Northwestern University. Her research focuses on economic issues in developing countries, including environmental conservation, gender equality, labor markets, health, and education. She earned a doctorate in economics from Harvard University, a master’s degree in physics and philosophy from the University of Oxford, and a bachelor’s degree in electrical engineering from MIT.

This article is adapted from an article she wrote for The New York Times, “Using the Airbnb Model to Protect the Environment.” ©2019 The New York Times Company.