Despite considerable improvements in recent years, the assessment of Sardinella aurita in West Africa is still hampered by problems. One of these is the lack of a reliable age determination of fish after the age of two years. The absence of precise information on the age structure of the population prevents the use of age-structured assessment methods such as Virtual Population analysis (VPA). As a substitute, production models are used that require only biomass estimates by acoustic surveys and catches in weight. Production models, however, do not provide information on recruitment variability. Also, their possibilities for stock prediction are limited. Stock assessment of S. aurita could probably be improved by using existing information on age composition, even if this is limited. Recent work on the growth of S. aurita has shown that length compositions may be split into a recruiting age group and an adult stock component. Using this simple split into two age groups, annual variations in total mortality and recruitment could be assessed.
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