Reproductive strategies of Plagioscion squamosissimus Heckel, 1840 (Osteichthyes Sciaenidae) in the Itaipu reservoir, Brazil

Abstract

Plagioscion squamosissimus is a dominant species in the Itaipu reservoir and has a significant role in the regional economy. The aim of the present research was the investigation of the curvina's reproductive strategies during the first years of the Itaipu reservoir (November 1983 to October 1989). Collections were undertaken from eleven sampling sites in the reservoir area, left bank tributaries, Paraná River and its tributaries. Species begin the reproduction in the area of influence of the Itaipu reservoir only in 1986. Size of early maturation, local and period of spawning showed gradual variations, with a broadening trend of this activity in the area, and thus guaranteeing success of the species. Mean size of early sexual maturation for the Plagioscion squamosissimus reached 16.2 cm for males and 17.8 cm for females.