Natural spawning and intensive culture of pejerrey Odontesthes bonariensis juveniles.

Address correspondence to: L.A. Miranda. Laboratorio de Ictiofisiología y Acuicultura. Instituto de Investigaciones Biotecnológicas Insituto Tecnológico de Chascomús (IIBINTECH), Chascomús (B7130IWA), Provincia de Buenos Aires, ARGENTINA. E-mail: [email protected] Received on April 1, 2005. Accepted on June 1, 2005. The pejerrey Odontesthes bonariensis is an atherinid fish native of the inland waters of Buenos Aires Province (Argentina). This species has also been introduced in other Argentinean provinces and some countries due to the economic movement generated by pejerrey game fish and aquaculture (Bonetto and Castello, 1985; Grosman, 1995; Mituta, 2001). Although pejerrey aquaculture is considered of regional importance, this activity has not been fully developed in Argentina. The culture of this species, either in extensive or semi-intensive systems, can be productive alternatives in the Argentinean Pampas where more than 2 millions square hectometers of lagoons have been described (Reartes, 1995; Espinach Ros et al., 1998; López et al., 2001). However, some reports have demonstrated the existence of problems in the feasibility of pejerrey farming: low growth rates, high mortality in the first stages and early sexual maturation before fish reach market size (Luchini et al., 1984; Grosman, 1995; Grosman and González Castelain, 1996; Gómez, 1998; Berasain et al., 2000; Colautti and Remes Lenicov, 2001; Miranda and Somoza, 2001). Then, it is necessary to perform basic and applied studies in order to establish pejerrey culture (Strüssmann, 1989; von Bernard et al., 2002). A main objective is to control reproduction in order to obtain a massive production of embryos and larvae and, if possible, almost all year round. Up to date, pejerrey seed production in Argentina is being performed only through the capture of wild f ish by gill nets and by artificial fertilization, according to traditional methodologies (Ringuelet, 1943), which cause the dead of all parent fish by manipulations. In the present work we summarize the results of our efforts to control pejerrey reproduction in captivity, for the development of efficient, economically viable and not pollutant techniques for the production of juveniles in an intensive system.