Nest survival of Crested Lark (Galerida cristata) in intensively used habitats in Central Poland

Abstract

AbstractBreeding success of birds depends on survival during two critical stages of the reproductive period: First, egg laying and incubation, and then nestling and fledgling. This essential element of avian life history mirrors an evolutionary adaptation of parents to existing environmental conditions. The main factors that determine nest survival involve weather, predation and sibling competition. Despite numerous studies documenting their impact on breeding success, only a few have analysed the issue with regard to ground-nesting birds and estimated their survival functions. Therefore, we decided to examine nest survival probability of the Crested Lark (Galerida cristata) in a population that occupies newly established roadside habitats in Central Poland. The analysis is based on 141 nests monitored between 2018 and 2022. We found that the mean survival probability of the whole nesting period was 0.376, and it was higher during the egg stage (0.836) than during the nestling period (0.392). The Cox proportional hazards model shows that nest survival in the nestling stage is mainly affected by the time of breeding and the distance from the road edge, and also by mean temperature of the whole nesting period. In other words, the probability of a brood failure in the nestling stage decreases as the breeding season advances, whereas it increases among nests located closer to the road edge. Furthermore, during the whole nesting period, nest failure decreases as the temperature rises. Our study suggests that the Crested Lark, being a multi-brood and thermophilic species inhabiting temperate regions, may benefit more if its nesting attempts begin later during the season when breeding conditions become more favourable. However, we also take into consideration a hypothesis that nesting in grassy habitats near road edges may prove to be an ecological trap, attracting high densities of nesting birds but leading to their low nest success.