Washington - Seven percent of a Costa Rican coffee farm's annual income - $62,000 - comes directly from the pollination "services" of adjacent tropical forest, according to a new study appearing today in the Proceedings of the National Academy of Sciences. The study is the first to quantify in such detail the economic value of pollination services from tropical forests.
"This study illustrates that there are compelling economic reasons for conserving native ecosystems," said Taylor Ricketts principal author of the study and director of WWF's Conservation Science Program. "Because the benefits we derive from ecosystems are difficult to quantify, they are often assumed to be worthless. Yet, we found that without this forest, the coffee plantation would lose about $60,000 in income from the diminished pollination alone."
Ricketts' team investigated pollination on coffee plants at three distances from the forest - near (330 feet), intermediate (one half mile), and far (just under a mile). The areas closest to the forest experienced more pollination by wild bees which increased coffee yields and decreased the number of deformed beans, compared to the plants farthest from the forest. Hand pollinated branches served as the control.
"Our numbers are very conservative because we just looked at one ecosystem service - pollination - on one farm," said Paul Ehrlich, a co-author and Bing professor of population studies at Stanford University. "If we quantified other ecosystem services like water purification, and the value of pollination to other neighboring farms, the value of this forest would be even greater."
The study found that the value of tropical forest is likely greater than other land uses for which forests are often destroyed. Cattle pasture, for example, would yield approximately $24,000 a year, less than half of what pollination services provides to the coffee plantation.
"The fact that pollination services alone are so valuable to an individual farm demonstrates how conservation is compatible with economic development," continued Ricketts. "Protecting natural ecosystems can benefit both biodiversity and local people."
Some governments have already caught on to this win-win situation, paying billions of dollars to conserve ecosystem services. New York City, for example, pays hundreds of millions of dollars to protect its watershed, far less than the billions of dollars it would take to build and maintain a water filtration system.