Nature preserves in at least two developing countries have reduced poverty among their human neighbors, according to a new study co-authored by IFPRI’s Kwaw Andam.

Communities living on the margins of national parks in Costa Rica and Thailand are better off than those not situated near the parks, say Andam and his fellow researchers. The finding eases concern that new parks reduce the incomes of nearby villagers because they ban or restrict farming and hunting. Such worries persist, the authors say, because “previous studies do not directly measure socioeconomic outcomes and do not use appropriate comparison groups to account for potential confounders.”

To be sure, communities near protected areas are poorer than national averages. But this is because they lie in remote areas to begin with, not because inhabitants live near parks. Indeed, by analyzing long-term poverty data and focusing comparisons on communities whose only or main difference is their distance from a protected area, the study demonstrates that poverty has fallen by 30 percent near parks in Thailand, and 10 percent in Costa Rica. In large measure, this is because parks create new jobs for game wardens and tour guides.

Will the findings prove as encouraging in countries that establish preserves but, unlike Costa Rica and Thailand, do not invest in parks and ecotourism? Researchers can use the study’s groundbreaking methodology to find out and, if needed, take action.

The study, “Protected areas reduced poverty in Costa Rica and Thailand,” appears in the May 25, 2010 issue of the Proceedings of the National Academy of Sciences of the United States of America.