Operational Parameters for the Aerial Release of Sterile Codling Moths Using an Uncrewed Aircraft System

SIMPLE SUMMARY: Pest management through the release of sterile codling moths from drones or uncrewed aerial vehicles (UAVs) represents an efficient method for distribution over orchards. In this study, moths released from greater altitudes were more broadly distributed and drifted more in strong winds compared to those released from lower altitudes. Most of the released insects were recaptured in a 50 m wide swath under the release route. Recapture rates from aerially released insects were 40–70% higher compared to those released from the ground. We found that an uncrewed aircraft system (UAS) releasing insects from 35 m above the ground in release routes 50 m apart outperformed standard ground release methods. UASs provide a promising alternative to ground release and conventional aircraft for the release of sterile codling moths. ABSTRACT: The codling moth is a serious pest of apples in most regions of the world where this fruit is produced. The sterile insect technique is one strategy used to control this pest and is employed as part of an area-wide integrated pest management program for the codling moth in British Columbia, Canada. Modified fixed wing aircraft are the most common method for the release of sterile insects in large area-wide pest management programs. However, aerial release with a full-size aircraft can be prohibitively expensive. We evaluated the use of small, uncrewed aircraft systems (UASs) for the release of sterile codling moths. Sterile codling moths released from greater altitudes were more broadly distributed and drifted more in strong winds, compared to those released from lower altitudes. Most of the released insects were recaptured in a 50 m wide swath under the release route. Recapture rates for aerially released insects were 40–70% higher compared to those released from the ground. UASs provide a promising alternative to ground release and conventional aircraft for the release of sterile codling moths.