THE EFFECT OF STOCKING DENSITY ON GROWTH IN THE GILTHEAD SEA BREAM, SPARUS-AURATA (L.)

The effect of stocking density on growth and size variability in gilth ead sea-bream, Sparus aurata (L.), was tested by growing juveniles at densities of 0.35 kg m(-3), 1.3 kg m(-3) and 3.2 kg m(-3). Fish in the highest density group grew 25% slower than fish in the lowest density group. The coefficient of variation of weight (standard deviation/mea n) did not change during the experiment. The effect of size variabilit y on growth rate was tested by creating groups with coefficients of va riation of weights ranging from 0.11 to 0.32, and glowing them at simi lar density (1.5 kg m(-3)). No differences in growth rates between gro ups were found. Only the more heterogeneous group showed a large decre ase in the coefficient of variation over time. It was concluded that g rowth in gilthead sea-bream, although negatively correlated to stockin g density, did not seem to be related to intraspecific competition as assessed by changes in size variability.