Comparative evaluation of efficient bird repeller distance between gas gun and sound bird repeller

Bird strike accidents mainly occur in the airport area. Reducing bird activities through bird repeller equipment is one of the main measures to prevent bird strike. In this study, two bird species with high-risk, pigeon (Columba livia domestica) and kestrel (Falco tinnunculus), were selected as the subjects and the gas gun and directional acoustic bird repeller were selected as the evaluation objects in Shenyang Taoxian International Airport. This study aimed to examine the behavioral responses of birds at different distances during the normal operation of these equipment to explore their effective distance and effects. The results showed that the vigilant and escape behaviors of pigeons and kestrels at 10 m and 30 m away from the gas gun bird repeller which were significantly higher than those of the control, while the number of these behaviors at 50 m away was not significantly different from that of the control. Pigeons and kestrels at 50 m and 100 m away from the directional acoustic bird repeller could significantly increase their vigilant and escape behaviors, whereas the repeller could significantly cause kestrels to increase their vigilant behavior at 300 m away. We concluded that the effective bird expel distance of the gas gun was 30 m, and the directional acoustic bird repeller could effectively expel to 300 m, and that the effect of the directional acoustic bird repeller on birds was stronger than the gas gun. Our results could provide a reference for the introduction and rational use of bird expel equipment in the airports.