Setting up interpretation criteria for juvenile and adult European anchovy otoliths from Canary Islands

Máster en Gestión Sostenible de Recursos Pesqueros

[EN] A standardisation of annual age determination in juveniles and adults for this species (Engraulis encrasicolus) is proposed. A total of 150 sagitta otoliths were selected for the analysis and annual increments were read in the postrostrum and antirostrum axes under a dissecting microscope on 25X. It was used three different treatments: water, alcohol and glycerine in order to get the best ring appreciation. All otoliths were aged three times by a single reader. The results not show high differences between the readings for the same one, or any treatments. Consequently, it is suggested bearing the economic part in mind to use water for later readings of the annual age determination of anchovy. Likewise one proposes the otolith validation by means of a new methodology where to determine the daily increments, checking that the determination realized in this work is correct.