Influence of Vegetation and Elevation on Nest-Site Selection and Reproductive Success in American Oystercatchers (Haematopus palliatus)

Barrier island habitats are increasingly threatened by climate change, with potential consequences for the breeding success and habitat quality of beach-nesting birds. Understanding fine-scale habitat requirements is important for identifying risks and managing these environments to support reproductive success. We evaluated two key habitat features, vegetation density and elevation, to understand their influence on American Oystercatcher (Haematopus palliatus) nest-site selection, hatching success, and fledging success on two Virginia (U.S.A.) barrier islands (Assateague and Assawoman Island). Using long-term nest monitoring data (2007–2022) and three years of remotely sensed elevation and vegetation data (2015, 2016, and 2021), we found that American Oystercatchers consistently preferred nest sites with lower vegetation density and at higher elevation. However, neither factor predicted hatching or fledging success. These results suggest that vegetation encroachment may contribute to population declines not by reducing reproductive output directly, but by limiting the availability of suitable nesting habitat. Vegetation nonetheless plays a key role in stabilizing high-elevation dune systems. Effective beach management should prioritize the preservation and creation of sparsely vegetated, elevated sites to maintain nest-site availability under changing coastal conditions.