Pheromone-based monitoring of invasive alien insects along the border of Finland and Russia – methods and unintentionally caught species

Global trade provides pathways for the spread of invasive species. To tackle the threat, many countries have designated surveys that are typically conducted at the probable ports of entry. For Finland, the most north-eastern region of the European Union (EU), such site is the border with Russia and the imports of coniferous roundwood and wood chips. In this paper, we describe the monitoring systems based on pheromone-trapping for three EU-wide quarantine pests: Dendrolimus sibiricus, Polygraphus proximus and Bursaphelenchus xylophilus. We also list the non-target species caught in an exploratory survey using pheromone traps. During the three years of survey, no quarantine pests were detected, but 30 other species of insects were caught. Therefore, the monitoring – despite not detecting the target pests – provided information about the abundance of other species. As insect diversity reflects the status of the surrounding environment, the value of such data should be increased via co-operation among research institutes.