There are even concerns that PES could backfire. Josh Donlan, a conservationist with Advanced Conservation Strategies, points out that a sudden influx of cash can disrupt local community structures. In Papua New Guinea some communities were paid several thousand dollars to protect leatherback turtles, but individuals left off the dole ended up killing the animals out of spite. Donlan and his colleagues have proposed "conservation mortgages" (pdf)—essentially microfinance loans or equipment loans whose terms are directly linked to biodiversity outcomes, such as endangered birds' hatching success.
Indeed, fairly compensating indigenous communities is going to be the most challenging aspect for REDD, which could effectively become the world's largest PES project. According to Barry Ferguson of the U.E.A., some conservation organizations are already in hot water with locals. For instance, the Wildlife Conservation Society (WCS) is involved in a pilot effort to market carbon credits in Madagascar via the Makira Carbon Co., yet Ferguson complains that the organization has never sought consent from indigenous communities living in the forests and has no mechanism to distribute revenues. However, James Deutsch, director of WCS's Africa Program, said that Ferguson was "not well-informed" and “the project is, and always has been, a deep partnership between the communities of Makira and WCS” with proceeds going to fund development projects. At the moment, however, scaling up of the Makira project has stalled due to a change in government.
Despite the challenges ahead, Michael Mascia, a senior social scientist at WWF and founder of the Social Science Working Group for the Society of Conservation Biology, finds the new links between conservation and human development promising. "Ten years ago," he says, "conservationists didn't know how to talk about this."