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Objective: The purpose of study was to identify environmental factors that influence downstream migration and passage of American Eels Anguilla rostrata in Roanoke Rapids Lake, a reservoir on the Roanoke River formed by the Roanoke Rapids Dam and Power Station. Methods: Yellow‐ and silver‐phase American Eels were outfitted with acoustic transmitters and monitored during four out‐migration periods from October 2019 through March 2023 using acoustic telemetry receivers placed in Roanoke Rapids Lake and the Roanoke River downstream of the power station. The timing of downstream passage through the power station was determined using acoustic detection data. Poisson regression models were used to analyze American Eel detections in the context of environmental variables that were hypothesized to cue out‐migration. Result: Out‐migration probability of American Eels from Roanoke Rapids Lake was influenced by time of day, rainfall, and change in lake level attributable to hydropower operations. Predictive models of out‐migration probability demonstrated that the number of migrating American Eels was widely variable across environmental conditions and was particularly sensitive to changes in lake level. Conclusion: The results of this study suggest that management actions, such as scheduled water releases from a dam and the consequent change in lake level (or correlated factors), can influence the onset and timing of American Eel out‐migration. Impact StatementAcoustic telemetry observations over multiple American Eel out‐migration seasons demonstrate that out‐migration patterns are influenced by time of day, rainfall, and lake level. The connection between out‐migration timing and changes in lake level attributable to hydropower operations suggests that water releases may be used to stimulate downstream passage through hydroelectric facilities during turbine outages, when survival is likely to be improved. [ABSTRACT FROM AUTHOR]

The eastern oyster (Crassostrea virginica), has experienced dramatic declines throughout its range, and most U.S. states along the Atlantic and Gulf of Mexico coasts have restoration programs. Oyster restoration in the Hudson River Estuary has been a focus of management agencies for over two decades. The present project was initiated in 2013 after sampling for replacement of the Tappan Zee bridge determined live oysters would be lost during bridge construction, thus requiring mitigation measures. Preliminary studies identified three areas for pilot studies to inform the design of full‐scale efforts. A pilot study involving deployment of oyster shell‐filled gabions and two styles of Reef Balls, found all substrates supported oyster recruitment and growth but there were higher oyster densities on gabions. Some of the gabions, however, failed structurally necessitating a need for new design. For full‐scale restoration, a total of 422 modified gabions and 881 Mini‐Bay style Reef Balls were deployed across three sites which totaled approximately 2.4 ha (6 ac) in seafloor area. Both substrate types were heavily colonized by oysters and several other species at all three sites, essentially duplicating the findings of the pilot study. The final monitoring event in 2020 indicated a total of approximately 5.8 million live oysters were on the substrates deployed in 2018. This mitigation effort was the largest oyster habitat restoration project in, or north of, the New York Harbor region in recent decades based on restoration area and several oyster metrics of early success. [ABSTRACT FROM AUTHOR]

The article presents a study that measures the value of altered mangrove wetlands as habitat for nekton. The composition, abundance, and spatial distribution of estuarine nekton assemblages in stable subtidal portions of tidal creeks and wetlands changed by construction of ditches were quantified through seasonal seine sampling. Results of the study suggested differences in the composition of species and abundance between natural and changed habitat.

The article investigates whether the abundance of juvenile blue crab varies between natural tidal creeks and man-made ditches in mangrove wetlands in Tampa Bay, Florida. Results suggest that juvenile crab abundance is highest in the man-made mosquito-control ditches, followed by the naturally formed tidal creek and lowest in stormwater-drainage ditches.