Workshop on the development of a spatial database and model for eels (WKSMEEL)

WKSMEEL is part of the roadmap defined by the WKFEA (Workshop on the future of eel advice). Experts from Japan, USA, Canada and Europe met to discuss modelling methods and the data necessary to support the development of a spatial assessment of the stock of European eel (Anguilla anguilla). Modelling of the European eel stock is envisioned as a two-level modelling process. At the regional level, it requires the implementation of statistical extrapolation models in freshwater habitats and specific models in lakes or lagoons. At the whole-stock level, a stage-based spatial model is envisioned. The rationale for choosing a stage-based approach for the global models and the requirements and validation of different regional models are discussed.

The data requirements for both regional and global stock models have been reviewed with a specific focus on spatial data. For the regional models, a common GIS data structure using broad scale river networks or national databases is proposed. This database should contain both water surface (lake, lagoons, transitional waters) and rivers. A database structure to store information on eel habitat, dam and electrofishing is proposed. The availability of GIS river database, dam data and electrofishing data is assessed at the European level, using survey questionnaires sent to national correspondents. For the global stock model, the data requirement, including the output of the regional models, have been defined.