Abstract

Spotted rose snapper (Lutjanus guttatus) is one of the most important commercial fish species caught in the Gulf of Nicoya; as a consequence, it has for many years been under heavy fishing pressure, mainly from a fleet of artisanal fishermen. From April 2015 to April 2016, a total of 1,109 specimens were analyzed to learn more about biological aspects and population dynamics of the stock distributed in the Paquera-Tambor Marine Area for Responsible Fishing (Paquera-Tambor MARF). Data gathered on the total length-weight relationship of the individuals in the sample showed that this species has negative allometric growth, and that the population consists of four cohorts. Mean size at first sexual maturity was estimated at 30 cm total length, and two maximum reproduction periods were estimated, the first from May to August, and the second from October to November. The estimated growth parameters were L∞ = 65 cm total length, K = 0.32 annually, and t₀ = -0.42. Mortality rates were estimated to be M = 0.68; F = 2.38; and Z = 3.06. The exploitation rate (E = 0.77) shows that the population is over-exploited. Stomach content analysis suggests that the population is made up of generalist feeders with preferences for crustaceans and fish.

Keywords: Lutjanus guttatus; snapper; Gulf of Nicoya; population parameters; feeding habits