AUTHORS: Lindsey A.P. LaBrie: Graduate Research Assistant (Ph.D.), Arkansas Cooperative Fish & Wildlife Research Unit, University of Arkansas, Department of Biological Sciences, Fayetteville, AR, 72703. Email: llabrie@uark.edu
Caleb P. Roberts: Unit Leader, U.S. Geological Survey, Arkansas Cooperative Fish & Wildlife Research Unit, University of Arkansas, Department of Biological Sciences, Fayetteville, AR, 72703. Email: cr065@uark.edu
ABSTRACT: Preventing new invasions from occurring is the most effective way to avoid the negative ecological, economic, and societal impacts of invasive species. Two established and highly related methods for preventing new invasions are horizon scans and risk screening. Horizon scans use expert consultation and consensus building to conduct rapid risk screening. Arkansas, like the rest of the U.S., is experiencing negative impacts of invasive species, and thus, there is a critical need to prevent new invasions and thereby avoid new negative impacts. Here, we met this need through three objectives: we 1) extracted risk screening results for fish in trade from the U.S. Geological Survey’s Horizon Scan of Vertebrates in Trade and adapted these results to Arkansas, 2) used the fish species screened in the USGS Horizon Scan to determine how climate matching scores shifted under future climate scenarios, and 3) developed a standardized workflow for risk screening for aquatic nuisance species in the United States that incorporates risk of establishment under future climate scenarios. To accomplish the first objective, we pulled risk screening scores (comprised of risk of establishment, invasion history and pathways, and potential negative impacts) for the 319 fish species identified in the USGS Horizon Scan. For the second objective, we used all fish species identified and screened in the USGS Horizon Scan. Then, using future climate models (Shared Socioeconomic Pathways models) for the years 2040, 2070, and 2100, we calculated climate matching scores between potential fish invaders’ native ranges and the climate in the U.S. For the third objective, we created a future risk factor scoring protocol for risk of establishment under future climate scenarios and applied the scoring to all fish species from Objective #2. Under current and future climates, only Prochilodus lineatus and Chondrostoma nasus received high risk scores in Arkansas. However, 11 species moved from low to medium risk under future climates, reflecting increased establishment potential. Most of the species that moved from low to medium risk are known invaders outside the U.S. and are known to have strongly negative ecological impacts in their introduced ranges, such as Clarias gariepinus, Abramis brama, and Hemichromis lifalili. Although climate change is increasing the potential for invasive species to establish in Arkansas, we show that prioritizing invasive species for prevention and watchlists is still feasible as the climate changes. Species identified as medium and high risk in this project are strong candidates for in-depth risk screening summaries and adding to an invasive species watchlist for Arkansas.