Storm-Induced Barrier Breach Effects on Species Distribution within a Temperate Estuary

Historically Great South Bay (GSB), NY was dominated by oysters, hard clams, menhaden and a diverse array of piscivorous fishes, but with reduced connectivity to the ocean the system has become dominated by lower trophic level species and upper trophic biomass has declined. In 2012, Hurricane Sandy created a barrier island breach increasing exchange with the ocean, providing an opportunity to evaluate changes to the ecosystem and species assemblages. We expect that higher salinity in GSB will result in greater occurrence of marine species and increased abundance of migratory fish and invertebrates. Results indicate an increase in species richness and diversity following the breach in GSB, yet the environmental drivers of these changes remain unclear. A generalized additive modelling approach will be used to estimate common species habitat preferences to environmental variables including temperature, salinity, dissolved oxygen and depth in order to predict species abundances or the likelihood that a given species would occupy a particular habitat, enabling evaluation of species’ response to habitat changes resulting from Hurricane Sandy. Overall, this research will explore the relationship between connectivity to the ocean and the role of stochastic alterations to the barrier islands as a likely driver in maintaining diverse nekton assemblages.