The conservation and protection of natural resources requires monitoring of temporal and spatial variability of ecosystem conditions, particularly with regard to human-induced stressors. The National Park Service (NPS) received a science mandate from Congress with the passing of the 1998 National Parks Omnibus Management Act and created the Inventory and Monitoring (I&M) Program. A primary role of the I&M Program is to collect, organize, and make available natural resource data and to contribute to the NPS's institutional knowledge by facilitating the transformation of data into information through analysis, synthesis, and modeling (NPS 2006a).