Spatiotemporal variation and driving mechanisms of nest predation on Spotted Doves along an urbanization gradient

Nest predation is a critical driver of avian reproductive success, yet its response to urbanization remains controversial. Using infrared camera traps to monitor 133 artificial nests and 32 natural nests of the Spotted Dove (Spilopelia chinensis) along an urbanization gradient in Nanchang and Shangrao, China, from 2021 to 2023, we examined spatiotemporal variation in predation pressure. We deconstructed predation pressure into risk (nest fate and survival time) and pattern (predation frequency, predator size, and predator–nest interaction duration). We found that higher urbanization and better nest concealment significantly reduced predation risk. The composition of the predator community did not change along the urbanization gradient, suggesting that the reduced nest predation risk in cities is likely driven by behavioral factors, such as the availability of alternative food or human shield effect, rather than by the filtering of predator species. In contrast, predation patterns were primarily moderated by season. The off-peak breeding season was characterized by more frequent but less severe predation events involving smaller predators and had shorter predator–nest interaction durations compared to the peak season. This seasonal shift opens a breeding window during the off-peak season, when lethal nest predation risk is reduced. The Spotted Dove's unique life-history traits enable it to capitalize on this opportunity by balancing environmental costs, enhancing its reproductive success and facilitating its colonization of urban environments.