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Shorebird reproductive success monitoring often relies on surveys of nest and brood survival. However, conclusions may be inaccurate due to the challenges of gathering and interpreting evidence of nest and brood fate. We tested the efficacy of in-person versus camera- based monitoring to quantify productivity and evaluate threats to reproductive success of American Oystercatchers (Haematopus palliatus) and Piping Plovers (Charadrius melodus) at Metompkin Island, Virginia. We deployed 73 cameras using three set-ups: at nests, at brood sites, and along a transect. The same areas were also surveyed in-person approximately once per week. Camera monitoring confirmed nest fate where in-person monitors could not determine fate from field evidence and provided insight to the effectiveness of mammalian predator removal. However, cameras failed to capture causes of mortality for mobile chicks and did not consistently document chicks where in-person monitoring confirmed successful broods. Cameras produced large quantities of data requiring 63.5–315 hours to review, depending on camera set- up. We found cameras were useful for validating conclusions from in-person monitoring, highlighting threats that surveys missed, and characterizing the predator community. Managers should consider the tradeoff between potential benefits and required effort of camera monitoring when deciding which method would be effective for meeting management goals.
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This content will become publicly available on February 1, 2027
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.
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- Award ID(s):
- 2425178
- PAR ID:
- 10684402
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- The Journal of Wildlife Management
- Volume:
- 90
- Issue:
- 2
- ISSN:
- 0022-541X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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