STUDY OF THE GROWTH OF SOUTHERN BLACK-AND-WHITE MONKFISH STOCKS

Growth parameters for black and white monkfish from ICES southern stoc ks, ICES Divisions VIIIc and IXa (Spanish and Portugese waters) were e stimated from age readings of the first ray of the dorsal fin (illicia ) sections and fitting the von Bertalanffy growth model. Black monkfis h growth parameters were obtained by sex and for sexes combined, from 336 illicia, between 1989 and 1993. The birthdate was assumed to be I January and back-calculation procedures were applied to infer the fish length at that time. Growth patterns differed by sex. and females att ain a greater body length. The growth parameters were also estimated f or combined sexes from the overall sample, and the sex-ratio of 1.3:1 (males vs. females) was considered to be representative of the exploit ed population. The growth parameters were: L-proportional to=101.69 cm , k=0.08 year(-1) and t(0)= -0.2 year. The white monkfish growth param eters were estimated for sexes combined from age reading of 165 illici a from fish caught in 1990 and 1993 in Spanish waters. The southern wh ite monkfish grows faster and attains a greater body length than the s outhern black monkfish. The growth parameters were: L-proportional to= 121.53cm, k=0.102 year(-1) and t(0)=0.032 year for the white monkfish. (C) 1997 International Council for the Exploration of the Sea.