Évaluation ou stock de sardinelle ronde (sardinella aurita valenciennes, 1874) senégalo-mauritanienne

Abstract

The Senegalo-Kauritanian Round Sardinella stock represents one of the main component of the catches obtained in Mauritanian and Senegalese waters which ranged, between the last twenty years, between 80-200 ths. tons. The basic parameters for the stock have been determined from the data collected on board the Romanian trawlers during 1972-1987. Length and age composition data indicated great fluctuation of recruitment from year to year, especially in the last ones. Growth parameters differ between authors despite of a relatively simile values for the mean length at age. The total mortality for the fully recruited age-groups ranged between 1.97-1.23 in the period 1981-1986. For a natural mortality of 0.55 the yield-per-recruit analysis indicates that the stock has been exploited at a level beyond tht giving the maximum yield-per-recruit. Both the trial and exploitable biomass show a continuous reduction from 1972 to 1987. The catch projection indicate a slow and constant tendency of improvement of abundance and biomass for the I989 and 1990.