First Comprehensive List of Non-native Species Established in the United States of America, Segregated by Major Regions

Harm caused by invasive species in the U.S. has been conservatively estimated at $120B annually, or four times the average annual cost of all severe weather events such as hurricanes, floods, and tornados. Invasive species are a subset of non-native species, and knowing what species are non-native to a region is a first step to managing invasive species. People have been compiling non-native and invasive species lists ever since these species have been causing harm, yet national non-native species lists are not universal, nor common. Non-native species lists serve diverse purposes: watch lists for preventing invasions, inventory and monitoring lists for research and modeling, regulatory lists for species control, and nonregulatory lists for raising awareness. This diversity of purpose and the listsâ variation in geographic scope make compiling comprehensive lists of established (naturalized) species for large regions difficult. However, listing what species are non-native (or alien) in an area helps measure Essential Biodiversity Variables for invasive species monitoring and mount an effective response to established non-native species. We reviewed 1,1674 resources to compile a non-native species list for 3 large areas of the United States: Alaska (AK), Hawaii (HI), and the conterminous lower 48 States (L48). The list contains 11,3441 unique names: 598 taxa for AK, 5,8485 for HI, and 6,6753 for the L48. The list is publicly available from the Knowledge Network for Biocomplexity and updated in an ongoing manner as non-native species become established in, or are eliminated from, the United States. It has been used to annotate non-native species occurrence records in the USGS Biodiversity Information Serving Our Nation (BISON, https://bison.usgs.gov), an all- species mapping application.