The potential for internet searches to track the first record of alien plant pest arrivals in Europe

Early detection of the arrival of invasive alien plant pests is essential for effective biosecurity. While official surveillance networks often detect new incursions, challenges persist in identifying pest arrivals early enough. We asked whether internet search data could potentially act as an innovative and cost-effective way to detect the first record of a pest species in a country. We extracted search data using Google Trends for 192 alien plant pest species across 21 European countries and compared internet search-derived first records with official first records to quantify whether internet searches could pick up incursions before the official first record date. Using null models to account for background noise in search activity, reliable first records derived from Google Trends were identified for only 22% of species examined and were more likely if the species was a quarantine pest or associated with agricultural hosts. The vast majority of internet-derived first records (~74%) were after the official first record date. Nevertheless, this lag was shorter for quarantine pests, pests associated with agricultural hosts, and species with more recent introduction histories. Our results indicate that Google Trends currently has limited utility as a stand-alone tool for the early detection of plant pest incursions. Nevertheless, internet search data may provide a useful complementary source of information for post-border surveillance, especially of highly regulated pests and species threatening agricultural crops. As internet use and public awareness continue to increase, the value of digital surveillance tools such as Google Trends for biosecurity monitoring is likely to improve.