Nest site characteristics and breeding success of the red-backed shrike (Lanius collurio) in agricultural landscape in eastern Poland: Advantage of nesting close to buildings

Abstract

One of the most important factors influencing breeding success in many bird species is predation. Nest site choice is one way of lowering the probability of such losses. In an agricultural landscape of eastern Poland, we examined the relationship between red-backed shrike (Lanius collurio) nest site characteristics, i.e., height above ground, concealment, and occurrence of thorns, and the risk of nest predation. We also considered the relationship with distance to potential predators, i.e., corvid nests, and the distance to buildings. Our results showed that only 1 environmental factor significantly influenced breeding success. Birds nesting closer to buildings achieved higher breeding success than those more distant from buildings. A positive correlation between date of first egg laying and distance from the nest to the buildings was also found. These results indicate that areas with human activities and buildings can created habitats that improve breeding success for some species. On the other hand, the growth of such habitats also contributes to decreasing availability of semi-natural areas for breeding and foraging for these species.