Economic and ecological impacts of invasive insect pests: Research efforts and knowledge gaps

Identification and quantification of those impacts are necessary to inform priority setting for prevention, eradication, and control of invasives. While economic impacts of invasive insect pests in agriculture are generally identified, quantification is difficult and research effort is unbalanced in relation to taxa, types of assessment, stage of the invasion process, geography and spatial scales. Ecological impacts are widely considered to be substantially underestimated for invasive insects in general, but particularly so for herbivorous pests that do not impact forest ecosystems. Our study systematically reviewed economic and ecological impacts associated with three globally relevant agricultural insect pests: Halyomorpha halys, Helicoverpa armigera, and Spodoptera frugiperda. Mechanisms of potential ecological and economic impacts were identified and search strings were developed to capture literature for each mechanism, and tailored for each species. These were used to conduct systematic reviews using the Web of Science platform. The results were analysed, compared and discussed in the wider context of existing knowledge, research effort, and knowledge gaps related to the study of economic and ecological impacts of invasive insect pests. This study raises awareness of underrepresented issues in these areas, and could inform future research towards a more holistic understanding surrounding the impacts of invasive species.