preliminar de Bahía Ascención,

Bahía de la Ascension is a bay with an area of 260 km2, located along the coast of the state of Quintana Roo, Yucatan Peninsula, Mexico. This paper provides a preliminary description of the marine ecosystem and its mass balance fluxes using the Ecopath with Ecosim software. Bahía de la Ascension is heavily influenced by mangrove and coral reef areas, and functions as a nursery area for important fishery resources (lobster, sharks, other fishes). A flow diagram, summary statistics and mixed trophic impacts of the groups in the ecosystem is provided. Results suggest that 22 % of the total system throughput consists of flows to detritus. The key resource in the ecosystem, due to the value of its catch, is lobster (Panulirus argus). The most abundant consumer group is benthic invertebrates. Better data for primary production, detritus biomass and detailed benthic invertebrate groups, as well as explicit consideration of seasonality would help to improve the model