Evaluating the status of European fish populations: A gallimaufry of recondite statistical techniques!

Robin Cook (University of Strathclyde, UK)

The status of fish populations is of interest not only to the fishing industry but also conservationists. A commonly held view is that most fish stocks are in decline. In this talk I will give an overview of the status of all species, commercial and non-commercial, occurring in European waters based on a range of statistical methods. The commercially valuable stocks are well studied but we have much less knowledge of minor species caught as bycatch or not caught at all. In this talk I will give an overview of the current management approach to fisheries and the modelling framework applied when assessing the main fish stocks where age structured models are the norm. I will introduce an alternative modelling approach for bycatch species that can be applied to abundance data but avoids the need for age structured data that is absent for most species. For species where quantitative population data are not available I will describe an ROC approach based on the IUCN classification system to infer conservation and exploitation status.