The number of human-simulated predators influences the escape behaviour of bird species in a West African protected area

Abstract

Continuous human presence in protected and recreational areas can adversely affect wildlife. Birds perceive the approach by humans as predatory and mostly flee in response, which can be energetically costly, and leads to disruption of foraging activities and interactions with conspecifics. This study used Flight Initiation Distance (FID) to assess bird responses to multiple versus single human approaches. We examined how the number of persons approaching the study bird species influenced the relationship between FID and factors such as flock characteristics, habitat features, bird orientation and alert distance. A total of 668 FID approaches were conducted on ten bird species belonging to nine families at Rennajj fish farm, Jos, Nigeria. Our findings reveal that the number of persons approaching birds significantly affected their risk assessment and escape behaviour, as they initiated flight earlier when approached by multiple persons. Focal birds positioned on water and ground exhibited significantly higher FID values than those in the tree or shrub habitats, indicating high visibility and vigilance by birds on the ground and water. Furthermore, study birds fled at significantly shorter distances during three-person approaches when oriented backwards, implying an increased vulnerability to predators approaching from the rear. We conclude that the number of persons approaching the study bird species, and environmental and spatial cues play significant roles in the threat perception of wild birds. These factors should be integrated into wildlife management to manage human disturbance effectively.