The common predator, Sheepshead (Archosargus probatocephalus), enhances survival of the Eastern oyster (Crassostrea virginica) in an experimental setting

Abstract

Oyster reefs are a vital but declining component of nearshore, estuarine ecosystems. Global efforts to restore this important habitat are ongoing but have had varied success. The potential for biotic factors such as predation to influence restoration trajectories is rarely considered; however, there is mounting evidence that a better understanding of trophic relationships could aid in the restoration of the ecologically critical Eastern oyster (Crassostrea virginica). A common predator-prey interaction within the oyster reef community was examined through manipulative experiments to determine what effect predator presence had on early survivorship of oyster spat – a factor known to influence the success of oyster reef restoration. The juvenile stone crab (Menippe spp.) is a known predator of spat (<30 mm) sized Eastern oysters but also serves as prey for mobile predatory fish. Sheepshead (Archosargus probatocephalus), a fish with a diet high in structure-associated invertebrates, are one of many predatory fishes that utilize oyster reefs. Adult Sheepshead presence was found to significantly increase oyster spat survival. Oyster spat survival can be attributed to both trait and density-mediated indirect interactions. These results suggest that changes in the presence of an exploited finfish species can influence oyster spat survivorship.