Reproductive modality and batch fecundity of the European hake (Merlucciusmerluccius L.) in the Bay of Biscay

Appraisal of reproductive modality is necessary to quantify the reproductiv e potential of a fish species. We believe that European hake, Merluccius me rluccius (L. 1758), may have an indeterminate fecundity modality because of (1) a continuum of oocyte sizes in the ovary of mature female hake during the whole reproductive season, i.e., no gap in the oocyte frequency distrib ution between immature and vitellogenic oocytes; (2) the maintenance of a s imilar diameter of vitellogenic oocytes throughout the spawning season; (3) a steady level of remnant total fecundity during the spawning cycle; and ( 4) the prevalence of atresia at the end of the spawning period. Batch fecundity of hake in 1994 averaged 165 eggs g(-1) (SE = 9.89) gutted female weight. Spawning frequency, based on the duration of different ovari an developmental stages, ranged from 0.052 to 0.189, which is equivalent to a batch interval of 19 to 5.3 days. Finally, a quantification of the per b atch and annual reproductive output was made.