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Context Reversing global declines of foundation species requires recovery of critical bottlenecks in population dynamics, particularly the recruitment of early life stages. Understanding the controls on recruitment can substantially improve restoration success. Objectives We investigated how geophysical conditions and restoration history determine recruitment in eastern oysters (Crassostrea virginica), a foundation species requiring substantial restoration efforts following severe, widespread losses. Methods Over 3 years, we measured annual oyster recruitment to standardized ceramic tiles on 9–16 intertidal reefs in coastal Virginia, USA. We paired these measurements with an 18-year time series of recruitment to natural substrate on 8 natural reference reefs and 44 restored reefs (0–16 years post-construction). Results Recruitment to tiles was highly correlated with recruitment to natural substrate, validating our methodology. Recruitment was positively spatially autocorrelated within 1 km and increased 9–14 × with moderate wind fetch. A one-meter increase in substrate elevation tripled recruitment. Recruitment was 4 × higher on natural reefs compared to restored reefs, regardless of elapsed time since restoration. Geospatial model predictions identified 6% (24 km2) of intertidal areas as highly suitable for oyster recruitment, offering a refined target for restoration practitioners. Conclusions By integrating multi-year field studies, long-term monitoring, and habitat suitability modeling, our research identified environmental conditions favorable for oyster recruitment, offering insights that could enhance restoration planning and population resilience. Our findings provide actionable insights for optimizing oyster restoration by targeting areas with favorable wind fetch and elevation. These results offer valuable guidance for spatial planning in restoration and may inform strategies for other species where recruitment limits restoration success. 

This dataset contains measurements of Eastern oyster (Crassostrea virginica) recruitment to standardized ceramic tiles deployed across intertidal oyster reef sites in the Virginia Coast Reserve. Recruitment is defined as the number of macroscopic oyster recruits (less than or equal to 25 mm shell height) per square centimeter of tile surface, capturing settlement and early post-settlement survival. Data were collected in 2018, 2019, and 2021 across 9-16 reef sites per year, including both natural and restored reefs. The dataset supports research on spatial and environmental drivers of oyster recruitment and has been validated against natural reef substrate data for comparability. 

This dataset has been superceded by Lusk, B., R. Smith, and M.C.N. Castorani. 2024. Oyster fauna lengths, counts, and biomass from restored and reference reefs in Virginia coastal bays, 2005-2023 ver 1. Environmental Data Initiative. https://doi.org/10.6073/pasta/d68de69f29cee5f737313a07f813f245 (Accessed 2024-02-22). which includes additional years and parameters. Oyster and associated reef fauna counts and lengths were sampled at 16 natural reference reefs and 61 restored shell plant reefs located at 18 sites in the Virginia Coast Reserve. Overfishing and disease decimated oyster reefs in the Virginia Coast Reserve in the 1900s. Reference reefs were defined as remnant reefs that naturally recovered in the early 2000s to develop the pronounced vertical structure and multiple oyster size classes that represent the desired endpoint of restoration efforts. Nearly every year since 2003, The Nature Conservancy and Virginia Marine Resource Commission have constructed oyster reefs in intertidal areas in the VCR. To construct the restored reefs, practitioners applied dredged, fossilized oyster shell to intertidal locations chosen for their bottom stability and accessibility (locations lacked oysters prior to construction). Whelk shell supplemented the oyster shell at 9 of the restored reefs. 

Oyster reef fauna counts and lengths were sampled at natural "reference" reefs and restored shell plant reefs located in the Virginia Coast Reserve. Overfishing and disease decimated oyster reefs in the Virginia Coast Reserve in the 1900s. Reference reefs were defined as remnant reefs that naturally recovered in the early 2000s to develop the pronounced vertical structure and multiple oyster size classes that represent the desired endpoint of restoration efforts. Nearly every year since 2003, The Nature Conservancy and Virginia Marine Resource Commission have constructed oyster reefs in intertidal areas in the VCR. To construct the restored reefs, practitioners launched dredged, fossilized oyster shell from barges to intertidal locations chosen for their bottom stability and accessibility (locations lacked oysters prior to construction). Whelk shell supplemented the oyster shell at some of the restored reefs. TNC practitioners monitor select restored and reference reefs annually for adult and spat live oysters, adult and spat box oysters, mud crabs, mud snails, oyster drills, live clams, and mussels.