When Policies Collide: The Landscape of Invasive Species Regulations
Reed, E. M. X., Cathey, S., Braswell, C., Agarwal, P., Barney, J. N., Brown, B. L., Heminger, A., Kianmehr, A., Salom, S., Schenk, T., Sharma, G., & Haak, D. C. (2023). The state of play in invasive species policy: Insights from invasive species laws and regulations in 21 US states. Bioscience. PDF.
Written by Emily Reed, edited by Sarah Bois
Summary
A strong, coordinated policy response at Federal, state, and local levels is needed to respond to invasive species. However, state policies are consistently inconsistent. In this study, Reed et al. compiled and analyzed policies relevant to invasive species in legal and regulatory codes for 21 eastern US states, from Maine to Florida. For invasive species laws and regulations, they evaluated (1) when states enacted these policies, (2) the number of policies in each state, (3) the percentage of policies that applied to exclusively aquatic environments, and (4) the number of invasive species explicitly identified in these policies. Most policies went into effect after the 1970s. This pattern was primarily driven by an increase in the number of regulations, which could indicate that state agencies are increasingly recognizing the importance of invasive species and their effects. They also found that many Northeast states had more invasion-related policies (as a proportion of the total number of policies) and more policies related to aquatic systems than southeast and south central states. This could mean that these states prioritize invasive species prevention and management more than their southern counterparts. Finally, they identified over 1000 unique species named in policies across all 21 states, 523 of which are listed as invasive in the US Register of Introduced and Invasive Species (US-RIIS) and the USGS Nonindigenous Aquatic Species (NAS) database. However, only two invasive species were named in all 21 states: creeping thistle (Cirsium arvense) and quackgrass (Elymus repens). In addition, invasive vertebrates were overrepresented in policies compared to those in the US-RIIS and NAS, while invasive invertebrates were underrepresented. These findings build on previous policy research related to invasive and noxious plant species (for example, see our research summaries on climate change and state invasive plant lists and lack of proactive policies for invasive plants).
Take home points
Coherent and coordinated policies among states are necessary for effective invasive species prevention and management, especially as climate change drives further species introductions.
Invasive species laws and regulations are inconsistent among east-coast US states, demonstrating a lack of coordination.
Only two invasive species, both terrestrial plants, are listed in policies for all 21 states, and invasive insect species are neglected in these policies.
Management implications
Lack of coordination among neighboring states, especially for which invasive species are regulated at the state level, can cause individual state policies to be less effective. Therefore, it is important to develop tools that allow resource managers to easily access policy information from other states.
Tools that facilitate data sharing and collaboration will be increasingly important in the future as climate change creates more suitable habitats for invasive species to expand northward
Related papers: Beaury et al. 2021, Bradley et al. 2022
Keywords: Invasive aquatic, Invasive plant, State regulation, Policy, Prioritization