Life history parameters of blue jack mackerel Trachurus picturatus (Teleostei: Carangidae) from north-east Atlantic

• Published in: Journal of the Marine Biological Association of the United Kingdom
• Main Authors: Garcia, Alexandra, Pereira, João g., Canha, Ângela, Reis, Dália, Diogo, Hugo
• Format: Article in Journal/Newspaper
• Language: English
• Published: Cambridge University Press (CUP) 2014
• Subjects: Aquatic Science; North East Atlantic
• Online Access: http://dx.doi.org/10.1017/s0025315414001751; https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0025315414001751

Blue jack mackerel Trachurus picturatus monthly samples were collected between 1998 and 2011 to determine morphometric relationships, maturity, growth rates, reproduction and spawning seasonality in north-east Atlantic waters (ICES area Xa2). A total of 2895 specimens were sampled, ranging from 98 to 542 mm in fork-length ( L F ). The morphometric relationships (length-length and length-weight) showed statistically significant differences between sexes. Ages were estimated by counting growth bands on otoliths and verified by marginal increment analysis, with specimens ranging from 0 to 18 years. The von Bertalanffy models used to estimate growth parameters for both observed and back-calculated length-at-age data gave good fits. The gonads were analysed macroscopically and the spawning season found to occur from December to May. The length at 50% maturity for females and males occurred at 277 mm L F (4.3 years) and 288 mm L F (5.1 years), respectively. The results provide important biological information for fisheries assessment of a species that plays an important key role in the surrounding ecosystem.