Flooding and a complex predator community drive American oystercatcher nest and chick survival in Virginia

Abstract On the Atlantic and Gulf coasts of the United States, conservation efforts for the American oystercatcher ( Haematopus palliatus ) commonly focus on improving reproductive success by identifying and managing key threats to nest and chick survival. However, these threats have the potential to change over time. We monitored the reproductive success of American oystercatchers in the Virginia barrier island system, a significant breeding site where annual American oystercatcher productivity has been low since 2016, suggesting evolving drivers of nest and chick survival. We routinely surveyed the nests and broods of breeding pairs from 76 active American oystercatcher territories on Metompkin Island in 2021–2022 and Fisherman Island in 2023. Additionally, we used radio‐telemetry to track one chick per brood ( n = 45 chicks) and improve our chances of identifying fate. Using models of age‐specific daily survival rates, we found that the probability of a nest surviving to hatching was high (0.91 ± 0.08 [SD]), relative to the probability of a chick surviving to fledging (0.51 ± 0.14 [SD]), indicating that low chick survival may be limiting reproductive success at sites in Virginia. Overall, American oystercatcher reproductive success was affected by a complicated set of factors, including flooding from tidal inundation and storm surge during the nesting stage, and the threat of predation from a complex predator community during the nesting and brood‐rearing stages. As threats to American oystercatcher reproductive success change in response to climate change and human activities, natural resource managers will need to consider ecosystem‐based management strategies to address those threats, such as habitat restoration to assist behavioral adaptation of nesting American oystercatchers to flooding, and control of threats from both mammalian and non‐mammalian predators.