Reproduction dynamics of Odontesthes aff perugiae( Evermann & Kendall, 1906) in Emboaba Lagoon, RS, Brazil (Pisces, Atherinidae)

Abstract

Reproductive aspects of Odontesthes aff. perugiae from Emboaba Lagoon, Rio Grande do Sul, Brazil, were analyzed in this paper. A total of 320 specimens was monthly collected from July/1989 to October/1990. The gonadal maturation curve was represented by the bimestral variation of the average gonadosomatic index values and showed that the reproductive period of this specie is relatively long, extending from July to December, with partial spawning. It was possible to note the period of young fish recruitment and to analyze the bimestral variation of the sex-ratio. The size of first gonadal maturation was estimated by graphic interpolation, resulting in 14.9 cm for males and 15.5 cm for females. The fecundity was considered low in relation to data available for other fish species, with values ranging from 470 to 1942 ovocytes. The estimate values of absolute fecundity were related with the biometric variables total length, total weight and gonadal weight, resulting in linear relationship for the weights and in linear for the lengths.