Seasonal catch per unit effort of pescada-do-Piauí­­, Plagioscion squamosissimus (heckel, 1840), Osteichthyes, Sciaenidae, in Ibitinga Reservoir (21º46’S í 48º59’W), Middle Tietê River, São Paulo State, Brazil, with informations on its occurrence

Abstract

From the beginning of July, 1989 through the end of June, 1990, in Ibitinga Reservoir, by means of exploratory fishing, it was verified that the pescada-do-piauí­­ (Plagioscion squamosissimusi) was present in every season of the year, being acclimatized to the reservoir, and that its capture per unit effort was as follows (in numbers of individuals): 9.1 in Summer; 3.5 in Autumn; 1.7 in Winter and 2.8 in Spring, and , respectively, in biomass: 1.936 kg; 0.658 kg; 0.550 kg and 1.133 kg.