Towards optimizing trap deployment for the detection of non-native scolytines in the United States

Bark and ambrosia beetles (Curculionidae: Scolytinae) pose a significant threat to forests in North America and around the globe. The USDA Forest Service Early Detection and Rapid Response (EDRR) program aims to detect recent establishments of non-native scolytines before they become widespread in the US. For the EDRR program to be most effective, trap deployment prioritizes sites associated with a high-risk of introduction (e.g., ports of entry, nurseries, urban areas). Across these high-risk sites, however, multiple abiotic and biotic factors, including climate and habitat characteristics, likely influence patterns of trap catch. Therefore, understanding how the environmental context of trap placement impacts trap catch can increase the likelihood of detecting future invaders. We utilized georeferenced data from the EDRR program spanning 2010 – 2019 to characterize how habitat variables (e.g., land cover, canopy cover, size of forest patches, ecoregion) and weather patterns (e.g., mean annual temperature, mean annual precipitation) affect the abundance and diversity of trapped scolytines. The results from this study, including models and maps, will aid surveyors in deploying traps at sites that maximize the probability of detecting non-native bark and ambrosia beetles.