Migration patterns of barramundi, Lates calcarifer (Bloch), in Papua New Guinea

Abstract

Adult L. calcarifer released in inland waters migrated to coastal spawning grounds. and those released on the spawning grounds returned to inland areas. Of 6369 fish tagged throughout western Papua, 978 (15.4%) recaptures were recorded, the maximum distance between release and recapture being 622 km. Tag recoveries indicated that these adult fish return to the same general area from which they originally migrated. Juveniles leave coastal nursery swamps when about 6 months old and by the end of their first year have become distributed throughout coastal and estuarine regions. During their second or third year they move into inland waters. although there is a residual population of all age classes that remains resident in coastal waters. Some 3-year-old, and a significant number of 4-year-old, fish undertake the annual migration from inland to coastal waters. Prevailing climatic conditions appear to affect the magnitude of this migration as not all of the adult fish migrate to coastal waters every year. Factors affecting this migration are discussed.