156 • Weeds Across Borders 2010 Early Detection of Invasive Species: A US National Park Service Approach

In 2008, the Eastern Rivers and Mountains Network (ERMN) and Northeast Temperate Network (NETN) of the US National Park Service (NPS) began early detection of invasive species surveillance monitoring throughout 20 parks in the Northeast Region. This monitoring effort is a component of the nationwide NPS Inventory and Monitoring Program. Early detection monitoring of incipient in-vasive plants, animals, and diseases was ranked among the top priorities in the ERMN and the NETN due to the known ecological impacts of invasive species on ecosystems, including loss of threatened and endangered species, altered community structure and composition of terrestrial and aquatic com-munities, and reduction in overall species diversity. While long-term changes associated with invasive species are being assessed through other monitoring protocols, it is also critical to detect new popula-tions of invasive species early in their invasion of incipient and sensitive habitats. Only when invasions are caught early will the chance of eradication remain high. Early detection monitoring in the ERMN and NETN includes three main components: (1) creation of individual park early detection species lists; (2) opportunistic surveillance monitoring of invasive plant and forest pest species that focus on educating monitoring field crews, cooperators, volunteers, and resource managers on invasive specie