Demographic models that have been proposed to describe the continental phase of eel life cycle can be divided into site specific and general models. Site specific models (see for example Vøllestad and Jonsson (1988) or De Leo and Gatto (1995)) are usually devised, calibrated and, in same cases, validated upon data from particular dataset. Such models help in describing local population dynamics but can be hardly applied to different populations. On the other hand, very general model (see Dekker, 2000 or Lambert and Rochard, 2007) can be easily applied to different contexts but usually neglect parameter calibration and prediction validation on field data. The aim of this thesis is to develop modelling approaches for describing eel demography that can be easily applied to different contexts where a suitable dataset is provided (chapters 2, 3, 4, 5 and 6). Then, I show the effectiveness of such models when defining management plans, requested by the new European regulation (EC 1100/2007), with particular emphasis on eel fisheries and multiobjective analyses (chapters 7 and 8).