Population structure, gonadal maturity and feeding habits of Eugerres plumieri (Gerreidae) in the pom-atasta fluvial-deltaic system, Mexico

Abstract

 Biological and ecological aspects of Eugerres plumieri were analyzed during an annual cycle from 1992 to 1993 in the fluvial-deltaic Pom-Atasta system associated with Términos Lagoon, Campeche (Mexico). It is a dominant species in the system, based on its numeric abundance, weight, high frequency and wide distribution. A total of 368 individuals were obtained, with a weight of 22,087 g and length ranging from 4.5 to 29.5 cm. The annual variation of the allometric coefficient b was from 2.727 to 3.3412. The condition factor varied from 0.393 to 1.0976. The population consists mainly of juvenile and adult individuals in gonadal stages I, II, III, IV, VI and VII, and more mature females than males were recorded after 17 cm. This species utilizes the system as a nursery, growth and feeding area. It has a varied trophic spectra and consumes at least 11 different groups. Its principal food items are ostracods, foraminifers, nematodes and tanaidaceans. It is a first order consumer. The Pom-Atasta system is located in a zone of intense fishing and oil activity, so it is important to advance in the knowledge of its fishing resources.