The spatio-temporal structure of a population of the deep-water shrimpAristeus antennatus on the fishing grounds off Barcelona, Spain, in the western Mediterranean Sea was studied, and the relationship between fluctuations in catch ofthis species and spatio-temporal changes in the size and sex composition of shoals is described. Fluctuations were monitored by using a sample design based on fixed seasonal sampling of three different habitats (upper submarine canyon, middle slope, and lower slope). The results explain changes in fishing fleet and fishing location. The stock appears to remain constant at approximately optimum levels ofexploitation because part of it is unexploited below 1,000 m. Factorial correspondence analy-sis indicated a generally strong influence of depth on the abundance of deep-water shrimp, explaining 63.14% of the variance. However, the influence of seasonality was stronger when only samples taken at depths shallower than 1,000 m (75.22%) were considered. Females contributed most to the catches on the upper and middle slope throughout the year, and catches of females were strongly related to seasonality (P<0.05). The combined interaction of depth and seasonality on the abundance of males was significant (P<0.05). Juveniles were present in the catches from autumn to spring, and the combined effect of depth and seasonality on the abundance of juveniles was also significant (P<0.05). The role ofthe regional submarine canyon as a zone of higher energy and biomass in the recruitment of this species is discussed, and the importance of spatio-temporal factors linked to the life cycle ofdeep-water shrimps is highlighted. The results demonstrate that comprehensive ecological studies of exploited species are essential to proper fisheries management

9 pages, 7 figures, 3 tables