Rethinking biological control programs as planned invasions

Invasive insect pests of agriculture in Canada cause extensive crop losses and have negative environmental impacts. The field of invasion biology is concerned with understanding what factors influence the arrival, establishment, spread, and environmental and economic impacts of these invasive species. For example, extensive theory has been developed and tested to explain what characteristics make a species invasive, and what features make habitats susceptible to invasion. In this article, we review recent advances in invasion biology that could help guide strategies to improve pest control with beneficial insects (natural enemies of pests). We argue that the characteristics and environmental factors that make pests invasive may be similar to those that favour successful biological control with natural enemies intentionally introduced to crop production settings to manage pests. We reveal that particular progress has been made in (i) the understanding of biological traits of successful invaders, (ii) how invasive species interact with other species in invaded areas, and (iii) how invasive species evolve in the years following introduction to a new area. Our review will help biological control practitioners see the use of natural enemies in crop protection from an “invader’s point of view”, leading to improved biological control success rates and minimizing impacts of invasive insect pests.