%0 Conference Proceedings %9 ACTI : Communications avec actes dans un congrès international %A Chassot, Emmanuel %A Fiorellato, F. %A Geehan, J. %A Floch, Laurent %T Improving the management of European Union and assimilated purse seine fleets size frequency data received by the Secretariat %C Victoria Mahé %D 2016 %L fdi:010067432 %G ENG %I CTOI %K OCEAN INDIEN ; EUROPE %N IOTC-2016-WPDCS12-18-Rev1 %P 15 multigr. %U https://www.documentation.ird.fr/hor/fdi:010067432 %> https://horizon.documentation.ird.fr/exl-doc/pleins_textes/divers17-01/010067432.pdf %W Horizon (IRD) %X Sampling and processing procedures used for monitoring the European and assimilated purse seine catch in the Indian Ocean evolved over time, particularly during the shery expansion throughout the 1980s. Size fre- quency data sets available include both raw and weighted size data as well as catch-at-size matrices. Here, we show that the size data used in the re- cent asessments of yellow n and bigeye with stock synthesis were derived from catch-at-size data while they should rely on weighted size data sets. Size structures between weighted and extrapolated data appear to be very similar during 1991-2015 and should not aect models estimates. By con- trast, size data available in the 1980s show major dierences which should be further explored. Future assessments performed for tropical tunas with stock synthesis will include updated versions of the purse seine size data that are currently key in the assessment of their status. %B Groupe de Travail sur la Collecte des Données et les Statistiques (GTCDS) = Working Party on Data Collection and Statistics (WPDCS) %8 2016/11/28-30 %$ 040 ; 020