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Fishery and Sea ResourcesFigure 5: Birthdate frequency distribution obtained from the 2005 survey data; black bars= peak of survivorship.sion analysis singled out a significant negativelinear relationship (F2,42 = 13.08; p= 0.001; r 2 = 0.24) only between temperatureand the juveniles anchovy mean sizefor each trawl.3.2 Birthdate, growth and mortalityof juveniles 2005The frequency distribution of all anchovyspecimens collected in 2005 showed a clearpeak between 65 and 85 mm (TL), alsoobserved in the sub-sample selected up tothe size of 130 mm TL which was usedfor the birthdate analyse. A two sampleKolmogorov-Smirnoff test showed thatthe sub-sample distribution was representativeof the whole population (p>0.3). Theage of examined fishes ranges between 50and 152 days with respectively 55 and 100mm observed TL. In the stability test forbirthdate distribution, the “abundance ratio”was high (0.67) indicating a relativelystable distribution [40]. The examinationof mortality model residuals showed thatthey were not randomly distributed aroundthe regression, particularly at older ages.Then, to avoid heteroscedasticity, it wasdecided to fit only data between 60 and 100days. Within this age range, the estimatedmortality rate was 0.0346 ± 0.01 d −1 . Theoverall birthdate distribution presents itsmodal value in early August while the bulkof anchovies hatched mainly between end-2062