Abstract: Nest-site selection is an important aspect of avian reproduction. How sympatric breeding species using similar habitat resources compete and coexist is a hotspot issue in avian ecological research. To explore the nest-site selection differences among sandpiper species breeding in the same colonies of Songnen Plain, we analyzed the nest measures, nest-site habitat characteristics and nest-site selection factors of sympatric nesting Black-winged Stilt (Himantopus himantopus), Pied Avocet (Recurvirostra avosetta) and Asian Dowitcher (Limnodromus semipalmatus) in Zhalong National Nature Reserve and its surrounding wetlands from May to June in 2022 and 2023. The results showed that the inner diameter and outer diameter of nests of Recurvirostra avosetta were significantly larger than those of Himantopus himantopus and Limnodromus semipalmatus, and that the outer diameter of nests of Himantopus himantopus was significantly bigger than that of Limnodromus semipalmatus. The number of plant species, average plant height and vegetation coverage around nests of Limnodromus semipalmatus, Himantopus himantopus and Recurvirostra avosetta decreased sequentially. Limnodromus semipalmatus nests were closest to other inter-specific and intra-specific nests, resulting in the highest nest density. Moreover, there were significant differences among nest distances to water surface and farmland of three sandpipers. Nest-site selection of all three species was influenced by vegetation and concealment factors, water availability, disturbance, and competition factors. However, the primary influencing factors differed among the species. The vegetation and concealment factors were the most important for the nest-site selection of Himantopus himantopus and Recurvirostra avosetta, while competition was the principal factor for Limnodromus semipalmatus.

Key words: nest-site selection, Himantopus himantopus, Recurvirostra avosetta, Limnodromus semipalmatus, Zhalong Wetland