Influence of Climate Change on Habitat Utilization of Chesapeake Bay Fishes

Habitat preference and climate-driven distributional shifts have been well documented for fishery resources inhabiting the continental shelf of the US East Coast, while little attention has been given to adjacent estuarine systems. The Chesapeake Bay serves as an important habitat for many fish species that represent a variety of life history modes and occupy unique ecological niches. Although the realized and projected effects of climate change on the physical environment of Chesapeake Bay have been evaluated, impacts on the fauna inhabiting this estuary have not been explored. Several species within the Chesapeake Bay, such as summer flounder (Paralichthys dentatus) and Atlantic croaker (Micropogonias undulatus), once supported robust commercial and recreational fisheries, however, fishery-independent survey data indicate that finfish utilization of the bay has diminished substantially in recent years.

The impacts of changing environmental conditions in the Chesapeake Bay on its associated fauna were evaluated using 16 years of data from the Chesapeake Bay Multispecies Monitoring and Assessment Program, a fishery-independent bottom trawl survey. A Bayesian analysis framework, specifically Integrated Nested Laplace Approximation (INLA), was used to develop habitat utilization models for selected species. Survey catch per unit effort was related to a suite of environmental covariates measured synoptically at each site to provide a baseline characterization of habitat preferences. Model projections incorporating expected future environmental conditions were generated to quantify impacts on available habitat resulting from climate change. Results of this study contribute important information to the growing body of literature on global change biology and to marine fishery resource managers facing policy development challenges amidst a changing environment.