Edinburgh Napier University

  The recovery of fishing grounds of Ucides cordatus populations in the Caeté Peninsula is a recurrent process due to individual movements. However, these movements could not be observed in the field. A pattern-oriented modeling approach was used to infer on U. cordatus individual behaviors from population-level observations. An individual-based model was specifically developed for this purpose. The model results informed that the reason of decision of movement of individual crabs was probably a local density-dependent process. Also, fitting the model to field spatial distribution patterns, this process could be seen as an intra-specific competition for nearby resources. It was hypothesized that the spatially structured organization of U. cordatus populations act as hierarchical buffer systems with nonfished high-density areas filling back the fishing grounds at different speeds. Density-induced movement may therefore be an important aspect for the sustainability of the U. cordatus fishery.