The fish assemblages of a striclty protected area and of a neighbouring fished area, located off a Mediterranean urbanized coast (Carry-le-Rouet, France), were compared in order to select the most evident, constant, and easily recorded indices of the "reserve effect". Visual censusing was repeated simultaneously at both sites eight time a year during 3 years along four permanent transects layed on shallow rocky bottoms (9-14m). Overall species richness was 16% higher in the reserve, but differences in average instantaneous richness were only marginally significant. The most contrasting results were shown bu the occurence frequency, abundance, and demographic structure of two types of target species. The type A target speciues group comprises 16 large meso- and macrocarnivores particulary threatened by spearfishing, inluding the commum nectobenthic sparids Diplodus spp. Type B target species are reprensented by two small territorial fishes particulary impacted by angling: the serranid species Serranus cabrilla ans the terminal phase males of the labrid Coris julis. The size structure of Diplodus ss., cabrilla, and C.Julis subpopulations strongly argues for the role of protected areas as a reservoir of large spawners. Fishing pressure is assumed to modify the social conditions of the C. julis local populations and to include earlier sex change.