Sardine series in PELGAS surveys : PELGAS 2000 to 2005
2005
Masse, Jacques | Duhamel, Erwan | Delaunay, Damien
Survey data from 2000 to 2004 were used to analyse whether sardine show a preferential distribution in relation to bottom depth and/or latitude. For this analysis, four strata were considered; North or South of latitude 46°N (separating VIIIa and VIIIb) and bottom depths deeper or shallower than 110m. Sardine length distributions are plotted as the proportion of small (< 18.5 cm) or big (larger than 18.5 cm) fish on the samples over the years. This division was chosen to take into account the bimodal structure of sardine length distributions (usually with a "valley" at 18.5 cm fish length). Small fish (mainly 1 year old) are generally found close to the coast and preferentially in the southern part. The year 2003 is different to the others but this year was totally atypical for all species and sardine was rather absent of the Bay of Biscay at the time of the survey.
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