摘要：Research related to the Endangered Species Act tends to take the presence of that policy as given and focus on issues of implementation and effects. This paper seeks to reconsider U.S. conservation policy entirely. The ESA does not protect species or ecosystems that are not endangered, and formally requires that conservation efforts be spread evenly across endangered species to prevent their extinctions. However, the focus of conservation science has evolved in recent years towards ecosystems and away from species. This paper characterizes the composition of optimal conservation spending when species are valued for their contributions to ecosystem services and not always for their own existence. The ESA clearly fails to provide ecosystem services when the species that provide them happen to be widespread enough not to be endangered. I show that the Noahs Ark design of the ESA is also unlikely to yield optimal conservation levels even of endangered species, and can push excess total social resources away from conservation and towards consumer goods. I show that private conservation can help to remediate inefficient distribution of government activity among species if the scale of government programs is modest enough to leave room for private initiatives to remedy accidental government misallocations. Finally, I suggest an alternative pair of policies that protect ecosystem services and match private expenditures on conservation of charismatic species.
