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Few stock assessments of elasmobranchs have been conducted in the Mediterranean due to the lack of available detailed and precise information. In recent years, in the Mediterranean Sea a major concern on the status of this group does exist and consequently scientists and managers have paid a major attention on the collection of data of fisheries in which they are involved as by-catch, on the impact of different fishing techniques, and on management issues aiming at reducing undesired removals. Information on landings for the more important species is now available in some Mediterranean countries but time series are still too short. Data on age structure of catches is often partial and does not regard all the fisheries in which the species are involved making difficult the reconstruction of the demographic structure of the commercial catches. So far such difficulties made almost impossible the use of age-based analytical models or surplus production models for stock assessment. Recently, stock assessments using simple approaches suitable for data poor stocks were performed for Raja asterias and Raja clavata, Scyliorhinus canicula and Galeus melastomus in the GFCM-GSA9. R. asterias is caught especially by trawlers fleet segments targeting flat fish (15-100 m of depth). R. clavata and S. canicula are in general part of the by-catch of a fishery operating at deeper waters (about 100-200 m) mainly targeting Parapenaeus longirostris, Eledone cirrhosa and Merluccius merluccius. G. melastomus is mainly found in the depth range 200-1200 m and is exclusively caught with bottom trawlers. It constitutes an important by-catch fraction of the Nephrops norvegicus fishery (250-500 m of depth) and the deep-sea shrimps fishery.