Variation in Avian Predation Potential on Insect Pests Across Time and Space Within a Small-Scale Agricultural Field: Implications for Applied Biocontrol

To feed a growing population, humanity will need to see an increased global agricultural output in crop production. One key strategy for achieving this goal is to reduce herbivory by insect pests, which is one of the leading causes of crop loss. Although there have been many strategies for combating insect herbivores, biological control may be the most sustainable in the long term. Birds in particular are potentially powerful biocontrol agents, but how avian predation varies within individual agricultural settings remains largely unknown. Here, we analyzed temporal and spatial variations in putative avian predation potential on insect pests in a small-scale agricultural setting. Our results show that the spatial distribution of predation potential is nearly uniform across a small field, indicating that birds with their vagility may be particularly well suited for applying constant, uniform coverage, at least across smaller landscapes. We also found that predation potential by birds varied significantly between seasons, with the fall showing the highest rate of predation. We discuss the applications of our findings for further studies investigating the biocontrol potential of natural bird populations and for leveraging such avian predation to help improve food production systems.