The purpose of the Endangered Species Act is to conserve threatened and endangered species, including sea turtles, and the ecosystems on which they depend. The act provides for listing species that need protection; designating habitat deemed critical to a listed species' conservation; protecting listed species against certain harms caused by federal and nonfederal actions; conducting 5-year reviews on species' status; and developing recovery plans that contain objective, measurable criteria that, when met, would result in a determination that the species can be removed from the list.