Integration of subsystems models as a tool toward describing feeding interactions and fisheries impacts in a large marine ecosystem, the Gulf of Mexico

This contribution documents, using the example of the Gulf of Mexico large marine ecosystem (GoM) LME, how mass-balance, trophic (‘Ecopath’) models can be synthesized into a single integrated, spatially explicit model, from which various inferences on the ecological functioning of, and fisheries impacts on an LME can be drawn. The 10 component models used here covered inshore subsystems (lagoon, coral reefs), shelves, the open waters of the GoM, both in Mexican and US waters, and the GoMs Central Gyre, and were integrated using the Ecopath with Ecosim software. The main features of the synthetic trophic model resulting from this integration are presented, along with several time dynamic (Ecosim) and spatial simulations (Ecospace). Jointly, their results suggest the GoM to be rather robust as a whole, although continued increases in fishing effort, especially by bottom (shrimp) trawlers, will have serious impacts, reverberating through the entire shelf subsystem.