A mass-balanced ecosystem model for the Kerguelen Plateau

Ecosystem models are useful tools for making informed management decisions regarding the potential effects of environmental change and fishing activity on Southern Ocean ecosystems. Recent work has successfully updated an existing Ecopath model for the Kerguelen exclusive economic zone from an unbalanced to a balanced model state (where energy inputs equal outputs). This balanced model details food-web dynamics in the Kerguelen Island region using species biomass and diet information. In this paper we present this balanced model as well as an evaluation of food-web structure and function using tools found in Ecopath. Energy flows in the model suggest that the Kerguelen Island food web is smaller and more mature than other sub-Antarctic food webs and the impacts of direct and indirect interactions on functional groups highlighted the importance of cephalopods in the food web. This model is currently undergoing an expansion to include the entire northern region of the Kerguelen Plateau.