Catch rates and catch structures of the Balfegó purse seine fleet in Balearic waters from 2000 to 2015; three years of size frequency distribution based on video techniques

Abstract

This study standardized the daily catch of the Balfegó joint fishing fleet from 2003 to 2015 and updated the unstandardized CPUE of the Balfegó purse seiners: both series are contrasted with the Japanese longline standardized CPUE series. The results showed that the unstandardized series is the only one that correlates with the Japanese index (r = 0,92). The age structure estimated from video techniques measured over the period 2013-2015 is consistent, showing that at the end of May in the Balearic grounds the fully recruited age is 11 years. The results were indicative that the 2002 year class was stronger than the 2003 or 2004 classes. We conclude that the unstandardized CPUE series of Balfegó vessels are a reliable abundance index of the ABFT eastern population and should be considered in the next assessment. Nevertheless, at present this statement should not be inferred to purse seiners’ catch rates from other Mediterranean regions.