Global drivers of historical true fruit fly (Diptera: Tephritidae) invasions

Abstract Given the high costs associated with fruit fly (Tephritidae) invasions, there is a need to better understand and predict the risks of future invasions. We assembled a global database of historical Tephritidae invasions with the objective to identify the biological and socioeconomic drivers that explain these invasions. We investigate the tendencies of certain species to invade and the characteristics of regions that make them more prone to invasions. We used various published sources and online databases to assemble a database documenting the occurrence (presence/absence) and status (native/non-native) of individual species for each country in the world. Values of several socio-economic and environmental variables were also assembled and considered as explanatory variables. A generalized linear mixed-effects model framework was used to evaluate the utility of these variables for predicting the country-level occurrence of each species outside of its native range. A total 44 species were identified as having been accidentally introduced in the world. Most species of invading Tephritidae have established in only five or fewer countries. The number of invasions has rapidly increased since the 1950s. Climatic similarity between native and invaded countries, gross domestic product of the invaded country and distance from the native range are significant predictors of tephritid invasions. Our analysis revealed that both economic and biological factors explain patterns of historical Tephritid invasions. Despite the rising efforts to prevent new invasions, additional species may continue to invade, and many currently established species will likely continue to expand their ranges into new areas.