Meta-analysis reveals that seed-applied neonicotinoids and pyrethroids have similar negative effects on abundance of arthropod natural enemies

The authors completed a meta-analysis to better understand the effects of neonicotinoid treated seed on natural enemy abundance relative to both foliar and soil pyrethroid treatments, and non-insecticide treated crops. The analysis of 28 studies found that neonicotinoid coated seed did reduce natural enemy abundance (roughly 16% abundance relative to non-insecticide treated controls). Furthermore, they found that neonicotinoid coated seed reduced natural enemies similarly to foliar or soil applied pyrethroids.  Beyond analyzing the broad impact of these pesticide use methods on natural enemies, the researchers looked more closely at what other factors impacted the changes in natural enemies. Insects (which are more susceptible to neonicotinoids) were more affected than non-insect arthropods (which are less susceptible to neonicotinoids). While they looked at whether scarcity of prey was part of what caused declines in abundance, there wasn't sufficient data to conclude that prey scarcity contributed to reductions in natural enemies. However, they did see trends suggesting prey scarcity could be playing a role.