A Pilot Ecospace Model for the Chesapeake Bay Region

Ecosystem Approaches to Management (EAM) are informed by understanding the simultaneous spatially-explicit interactions among multiple species in an ecosystem.  Ecosystem simulation models can provide a valuable tool to support EAM in the Chesapeake Bay region, where several species have already been targeted for ecosystem based fishery management plans.  Here we present an Ecospace model for the Rhode River, a tributary to the Chesapeake Bay.  An Ecospace model simulates the trophic dynamics of an Ecopath with Ecosim model in a spatial context, allowing predator and prey species to move among spatial cells based on habitat use.  Multiple empirical datasets were gathered to build the model including data on fish population size, fish length, benthic habitat type, and benthic biomass.  Other parameters in the model were estimated from the literature.  The model demonstrates the importance of choosing appropriate spatial scales in model development, the role of habitat heterogeneity in trophic dynamics, and the role of biomass imports and exports into and out of the system.  Using the knowledge gained from the Rhode River model, an Ecospace model for the whole Chesapeake Bay will be constructed to provide a useful tool for managers as the Bay region moves toward EAM.