Bird damage management in vineyards: Comparing efficacy of a bird psychology-incorporated unmanned aerial vehicle system with netting and visual scaring

Abstract

Bird damage to fruit crops is a significant problem and incurs great cost due to product losses on an annual basis. In this study, Unmanned Aerial Vehicles (UAVs or drones) that incorporated the principles of bird psychology were used to measure the efficacy of deterring pest birds in vineyards. Earlier experiments measuring bird responses to UAVs demonstrated successful deterrence to a variety of bird species. To study efficacy, the same UAV method was applied in conjunction with another bird-scaring method involving static visual devices, as well as the netting method. The methods were applied concurrently in delineated treatment blocks within the same vineyard for a 7-day period and this comparison was repeated at three different locations. Bird damage was visually estimated and recorded as average percentage damage within grape bunches. In summary, percentage damage to bunches within treatment blocks: (1) UAV, (2) visual scaring, and (3) netting was: 0.9%, 1.8% and 1.2% at the first location; 1.6%, 2.5% and 0.7% at the second location; 1.2%, 4.8% and 0.5% at the third location. Statistical analyses showed that damage experienced in the UAV deterrent and netted treatment blocks were similar across locations. In contrast, the visual scaring treatment block experienced significantly more damage than the netted treatment block at each location. Efficacy of the UAV deterrent could be further improved by broadcasting distress signals that are specific to the pest species. The cost-effectiveness could be greatly improved by making the system autonomous in the future thereby removing the need for direct human involvement and saving labour costs.