Sea trout,
Cynoscion jamaicensis
, is an important fish in artisanal and industrial trawl fisheries of Northern Paria Peninsula, and knowledge of its population parameters is required to establish management plans of its exploitation. The sample consisted of 852 individuals, collected on board of industrial shrimp trawlers between January and December 1997. The biometry and macroscopic gonad maturity stage of each individual were evaluated. Average size was similar between sexes, with a general average of 241 mm of total length (T
L). Parameters of the weight - length relationship did not differ significantly between sexes, and a common regression was estimated as W = 5,147 x 10
-6 T
L3,151, in which the relative growth factor (b) was significantly greater than 3. The condition factor (Kn) remained near or greater than 1 during the study period, with the largest values observed in March and August-December, corresponding to periods of greatest gonad development and sizes of individuals. The minimum size of first maturity were registered at 153 and 206 mm T
L for females and males, respectively. The size at which 50% of the population is mature did not differ significantly between sexes, and was estimated at 251 mm T
L. Beyond 265 mm T
L, more than 75% of individuals were sexually mature. Considering that the size at which the population reaches maturity is larger than the mean size of the exploited population by the industrial shrimp trawlers, it is expected that the species' density undergoes severe deterioration in the zone, if indiscriminate capture of individuals is maintained.