IOSSS - ESPADON - Etude de la structure du stock d'espadon de l'Océan Indien: Synthèse de la première année. Période novembre 2008 - décembre 2009

Based on genetic and biological dynamic approaches, the main objective of the IOSSSESPADON project (2009-2011) is to study the biology and the stock structure of the Swordfish (Xiphias gladius) in the Indian Ocean and the bordering oceans (South East Atlantic and West Pacific). The results of this project will greatly contribute to a better stock assessment of this species that is undertaken by fisheries management commissions, mainly the IOTC. The first year of the project was dedicated to finalize the sampling strategy, to elaborate the associated protocols and to implement a large balanced sampling shame organised around a stratified spatio – temporal effort (2 sampling seasons: April – June and October – December) in the whole Indian Ocean. Based on a cooperative approach, a sampling network composed of 7 national and international partners, the IOSSS-ESPADON project allowed collecting 2365 swordfish length, 1100 genetics samples, 391 isotopes samples, 950 gonads for sex and maturity stages identification, 269 stomachs contents and 324 otoliths for chemical analysis. This first year also allowed to (i) create new cooperation’s for 2010 in order to cover strategic sampling area for stockdiscrimination not already sampled in 2009 (ii) create a database associated to a data quality management process (iii) Develop a microsatellite library of 18 new microsatellites that will be used in the genetic stock structure approach. The second year (2010) of the project has the objective to follow up the sampling strategy at the Indian Ocean scale and to undertake the analysis of the data collected in 2009. At the end of this second year, a first global analysis should be processed for each component of the project: the genetic, the isotope and the reproductive dynamic ones. The last year of the project (2011) will allow processing a multivariate analysis of the data collected along the IOSSS-ESPADON project.