lydemapr: an R package to track the spread of the invasive Spotted Lanternfly (Lycorma delicatula, White 1845) (Hemiptera, Fulgoridae) in the United States
A crucial asset in the management of invasive species is the open-access sharing of data on the range of invaders and the progression of their spread. Such data should be current, comprehensive, consistent, and standardized, to support reproducible and comparable forecasting efforts among multiple researchers and managers. Here, we present the lydemapr R package containing spatiotemporal data and mapping functions to visualize the current spread of the spotted lanternfly (Lycorma delicatula, White 1841) in the Western Hemisphere. The spotted lanternfly is a forest and agricultural pest in the eastern Mid-Atlantic region of the U.S., where it was first discovered in 2014. As of 2022, it has been found in 12 states according to state and federal departments of agriculture. However, the lack of easily accessible, fine-scale data on its spread hampers research and management efforts. We obtained multiple memoranda-of-understanding from several agencies and citizen-science projects, gaining access to their internal data on spotted lanternfly point observations. We then cleaned, harmonized, anonymized, and combined the individual data sources into a single comprehensive dataset. The resulting dataset contains spatial data gridded at the 1 km2 resolution, with yearly information on the presence/absence of spotted lanternflies, establishment status, and population density across 658,392 observations. The lydemapr package will aid researchers, managers, and the public in their understanding, modeling, and managing of the spread of this invasive pest.