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In our ongoing bay scallop restoration efforts in eastern Long Island, NY, United States, we have planted millions of hatchery‐reared juveniles to serve as broodstock when they mature. These plantings have driven the resurgence of larval recruitment, benthic population sizes, and commercial fishery landings over a 12‐year period. In this article, we detail an attempt to track the contribution of our restoration efforts to population rebuilding using planted "skunks," an uncommon color morph, by looking for increased skunk frequencies in subsequent wild cohorts. Although we saw higher skunk frequencies among large juveniles in natural populations in the first 3 years after extensive skunk plantings, supporting use of uncommon color morphs as a passive tracer, this conclusion was not supported when examined over a 12‐year period, as no strong correlations were seen between skunk frequencies at different life stages (adult broodstock, small and large F1 juveniles, F1 adults) for respective cohorts. Potential reasons for poor correlation between skunk frequencies and restoration efforts include lower than expected production of skunk offspring, dilution of out‐planted contribution to growing natural populations, interannual variability in skunk frequencies that may have obscured the expected skunk signal, and/or differentially higher mortality of skunks at postset and larger juvenile stages. In the latter case, skunks experienced higher overwinter mortality, most likely due to predation, in 9 of 11 years. This led us to suspend skunk plantings after 3 years. Nevertheless, commercial fishermen perceived skunks to be "our" scallops, helping raise the profile of and support for our restoration efforts. [ABSTRACT FROM AUTHOR]

Eelgrass, Zostera marina, is generally regarded as the preferred habitat of bay scallops, but in some cases scallop populations have persisted or increased in areas lacking eelgrass. This suggests that some other substrate(s) may serve important ecological functions for bay scallops. One candidate is Codium fragile, a macroalgal species with which bay scallops are known to associate and in which we commonly find juvenile and adult bay scallops in eastern Long Island, New York. In this study, we examined whether survival of planted bay scallops differed in Codium, eelgrass, and Codium + eelgrass substrates at two sites during August and October of 2 years. Survival of tethered scallops and recoveries of live free-planted individuals varied with scallop size, planting season and year, but no differences were observed between the three substrates for a given scallop size and planting date. Crab (particularly Dyspanopeus sayi) and whelk predation were implicated as important causes of tethered scallop mortalities while emigration and removal by predators likely contributed to scallop losses. Densities of naturally recruited 0+ years scallops recovered by visual and suction dredge sampling were similar in the eelgrass and Codium substrates. While our results suggest that Codium may offer some degree of predation refuge for bay scallops, further work needs to weigh the potential disadvantages of this substrate (such as low DO levels, potential attachment and transport of scallops, and differences in current flow, food availability and sedimentation relative to eelgrass) to determine if Codium may serve as a valuable habitat for bay scallops throughout their lifespan. [ABSTRACT FROM AUTHOR]

The consumptive and nonconsumptive effects of predators on their prey and the indirect effects of these interactions that cascade through food webs have been studied for over half a century. In the northwest Atlantic, the stock of black sea bass (Centropristis striata) steeply declined during the 1980s. While population crashes of fished bivalve species coincided with those of black sea bass, the role of black sea bass in driving trophic cascades that indirectly influence bivalve survival has largely been overlooked. Over the past decade, black sea bass have not only been recovering in abundance but warming water temperatures have been driving a northward expansion of the extent of their seasonal migration, resulting in a particularly strong relative recovery along the south shore of Long Island, New York. To explore whether black sea bass alter the foraging rates of mud crabs (Dyspanopeus sayi) on a species of bivalve, blue mussels (Mytilus edulis), we manipulated the presence and position of sea bass within an array of mesocosm tanks. We found that the presence of black sea bass reduced the proportion of blue mussels consumed by mud crabs. Black sea bass presence indirectly elevated blue mussel survival by as much as 47.7% by reducing mud crab per capita consumption of blue mussels by 57.9%. However, there were limitations to the nonconsumptive effects of black sea bass that appeared to depend on their proximity to mud crabs. While our results are from an experimental setup with a simplified food chain and are context dependent, they emphasize the importance of studying how nonconsumptive effects of specific marine predators influence trophic cascades from both conceptual and applied coastal resource management standpoints. Our results suggest that the recovery of black sea bass may bode well for the population restoration of several species of bivalves within estuaries throughout their range. Further, our study provides evidence that indicates that the nonconsumptive effects of a recovering marine predator can indirectly elevate the survival of a basal food resource species. • Presence of a fish predator produces a trophic cascade that increases bivalve survival. • Crabs reduce their feeding rates when a fish predator is present. • There are limitations to the effects of the presence of a fish predator. [ABSTRACT FROM AUTHOR]