A science-based approach to regional conservation planning

Although single-species approaches have played an important role in conservation in the United States, the Endangered Species Act provides a mechanism for conservation at larger scales through Habitat Conservation Plans (HCPs). HCPs not only offer the potential for comprehensive conservation planning for a wide range of species across broader geographic scales but also provide assurances that eliminate risks related to endangered species concerns for nonfederal landowners, developers, and planners. Given their benefits, dozens of municipalities have adopted HCPs to address planning issues related to rare and vulnerable species. The challenge, however, is to develop conservation plans that reliably meet broader-scale conservation and planning objectives while not increasing risks posed to vulnerable species. Consequently, we designed a science-based framework from which to develop regional conservation plans, including HCPs. We designed a rigorous process that classifies areas based on their relative conservation value as part of a conservation strategy for more than 20,000 km² of Sonoran desert in Pima County, Arizona. This chapter describes our approach including the fundamental planning elements selected, the process used to quantify the relative biological importance of each landscape unit, and how we assembled landscape elements into units that form the framework of the Sonoran Desert Conservation Plan.