Fish ageing by otolith shape analysis

Depletion of our fish stocks due to overfishing is undoubtedly the single most important problem facing the fishery industry world-wide. Knowledge of the age profile of a fish population is of primary importance for stock assessment and thus for stock management. The purpose of this study was to develop and evaluate objective and robust fish ageing methods based on twodimensional images and on three-dimensional shape and density distributions of otoliths. In the course of the project a large database of otolith shapes was established for a number of important species. The database has been used to test newly developed methods and algorithms in the context of this project and it will continue to serve that purpose for new methods to be developed in the future.