Age-0 bluefishPomatomus saltatrixwere widely distributed and seasonally abundant in shallow beach habitats of Narragansett Bay, Rhode Island. Based on length-frequency data that were polymodal in some years, these age-0 fish comprised spring- and summer-spawned cohorts. Cohort-specific measures of abundance, growth, total mortality and emigration, and size were determined for 1982–1992. In all years, spring-spawned fish dominated the catch from at least July to September. For this cohort, annual abundance varied by an order of magnitude, growth ranged from 0.9 to 2.1 mm/d, total mortality and emigration rates were between 0.2 and 2.8%/d, and mean length on October 1 ranged from 164 to 248 mm fork length. Spring-spawned fish were about twice as large as summer-spawned fish by October. Summer-spawned fish also occurred less frequently and in lower abundance. These findings confirm that Narragansett Bay is an important nursery for bluefish, and that the trend toward declining annual abundance measured in this bay is concordant with the reported decline of bluefish throughout the western Atlantic. Correlation analysis with data for only the spring-spawned cohort suggested density-dependent (i.e., compensatory) processes occurred; growth decreased monotonically but not linearly, relative to abundance, whereas combined mortality and emigration rates increased linearly. Measures of abundance were also a function of seine-net size; seines less than 25 m long were particularly ineffective for collecting age-0 bluefish. These relationships suggest that monitoring age-0 fish in estuaries may help predict future population size.