Use of frequency analysis methods to estimate growth of anchovy ( Engraulis encrasicolus L. 1758) in the Gulf of Cádiz (SW Spain)

Abstract

This paper presents the first estimates of growth parameters for anchovy, Engraulis encrasicolus in the Gulf of Cádiz (SW Spain). Time series of monthly length frequency samples from 1989 to 1993, collected in three fishery ports of the Gaditanian Coast were used. The seasonal von Bertalanffy growth model and length frequency analysis methods were applied to estimate anchovy growth parameters L ∞, k, C and t s by the use of ELEFAN I and Powell–Wheterall methods. The mean parameter estimates were L ∞=18.95 and k=0.90 per years by ELEFAN I and L ∞=18.69 and k=0.90 per years by Powell–Wheterall method. Length–age keys were estimated and used to describe fishery trends. Length at one-year old was estimated to be between 11.14 and 11.31 cm. Results suggest that this stock is primarily supported by the smallest age groups, showing a strong dependence on recruitment.