Does Invasion Science Encompass the Invaded Range? A Comparison of the Geographies of Invasion Science Versus Management in the U.S.
Abstract
Biases in invasion science have led to a taxonomic focus on plants, particularly a subset of well-studied plants, and a geographic focus on invasions in Europe and North America. While broader, country-level geographic biases are well known, it is unclear whether these biases extend to a finer scale. This study assessed whether research sites for ten well-studied invasive plants in the U.S. are geographically biased relative to each species’ known invaded range. We compared the distribution, climate, specific geographic variables related to land type (public or private), proximity to roads and universities, and state noxious weed status of research sites reported in 735 scientific articles to the locations of manager records from EDDMapS and iMap Invasives. We attributed each scientific article to one of five study types: impact, invasive trait, mapping, management, and recipient community traits. While the number of research sites was much smaller than the number of manager records, they generally encompassed similar geographies. However, research sites tended to skew towards species’ warm range margins. For all but one species, at least one study type encompassed a significantly different climate space from manager records, suggesting that some level of climatic bias is common. Impact and management studies occurred within the same climate space for all species, suggesting that these studies focus on similar areas—likely those with the greatest impacts and management needs. Manager records were more likely to be found near roads, which are both habitats and vectors for invasive plants, and on public land. Research sites were more likely to be found near a college or university. Overall, we did not find evidence for substantial geographic biases in research studies of these well-studied species, suggesting that researchers are generally doing a good job of exploring the impacts, traits, and management implications of invasions across the extents of the invaded range. However, the consistent climatic biases and spatial clustering of specific study types suggests that researchers and managers should use caution when developing inference for understudied geographic areas.