Behavioural responses of Bonelli's eagles to human disturbances: Assessing the effect on reproduction and suggested mitigating measures

Abstract There has been increasing recognition of the adverse effects of outdoor recreation on the behavioural ecology, breeding success and ultimate abandonment of territories in several raptor species, such as the Bonelli's Eagle ( Aquila fasciata ). We assessed the effects of human activities on the behaviour and breeding success of Bonelli's eagles breeding in south‐eastern Spain, using a 14‐year long‐term data set. Our results showed a weak behavioural response to human activities. The probability of eagle reaction varied among the human activities assessed and increased when they occurred close to a nest, being most marked for ecotourism activities. In general, the probability of a bird reacting increased sharply when an activity occurred closer than 480 m from the nest, but reactions were negligible when an activity occurred 1000 m away. Ecotourists only affected Bonelli's eagle behaviour at distances <300 m from the nest. We found a negative relationship between human activity and Bonelli's eagle behaviour: the probability of a reaction decreased with the increasing frequency of human activities, suggesting a degree of eagle habituation. Breeding success did not vary with a pair's experience of disturbance, nor between the periods before, during and after the COVID‐19 lockdown but did increase with the frequency of human activities. Our results indicated that Bonelli's eagles can develop a degree of tolerance to human activities during the nesting season. This behavioural plasticity offers the opportunity to harmonize anthropogenic activities with the application of specific conservation measures for this species in humanized landscapes. Our findings led to suggestions to minimize the detrimental effects of human activities and to optimize the conservation management of Bonelli's eagles in Southeastern Spain. More generally, our study emphasises the value of behavioural ecology studies for guiding conservation. Read the free Plain Language Summary for this article on the Journal blog.