REPRODUCTIVE DYNAMICS of THE MAIN SPECIES of FISH IN THE MUNICIPAL RESERVOIR of SAO JOSE do RIO PRETO

The objective of this study was to investigate the reproductive dynamics of fish of the Characidae (Serrapinnus notomelas, Hemigrammus marginatus, Hyphessobrycon eques, Piabina argentea, Steindachnerina insculpta) and Poecilidae (Poecilia reticulata) families in the municipal reservoir of Sao Jose d...

ver descrição completa

Detalhes bibliográficos
Autores: Linhares de Andrade, Vanessa Xavier [UNESP], de Faria e Souza Campos, Fabio [UNESP], Langeani, Francisco [UNESP], Romagosa, Elizabeth
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2008
País:Brasil
Recursos:Universidade Estadual Paulista (UNESP)
Repositorio:Repositório Institucional da UNESP
Idioma:inglés
OAI Identifier:oai:repositorio.unesp.br:11449/42220
Acesso em linha:http://hdl.handle.net/11449/42220
Access Level:acceso abierto
Palavra-chave:Characidae
First Maturation
Populational Structure
Reproductive Dynamics
Reservoir
Poecilidae
Descrição
Resumo:The objective of this study was to investigate the reproductive dynamics of fish of the Characidae (Serrapinnus notomelas, Hemigrammus marginatus, Hyphessobrycon eques, Piabina argentea, Steindachnerina insculpta) and Poecilidae (Poecilia reticulata) families in the municipal reservoir of Sao Jose do Rio Preto, SP, Brazil. The populational structure was evaluated with regard to sex ratio, classes of length, and the estimate of the mean size of the specimens at first maturation, from February 2002 to January 2003. The sex ratio was similar for S. notomelas, H. eques and P. argentea. However, for the other three species, the difference between males and females was higher than 5%. The captured species, with the exception of P. argentea, exhibited significant differences between the sexes in the month that follows the rain season. It was also verified that the males of the studied species, with the exception of P. reticulata, were predominant in the lower classes of length. For S. notomelas, H. eques and S. insculpta, the males showed higher values of L(50) than the females, the opposite of what occurred with the only species of Poecilidae captured, possibly because they are viviparous and keep the embryos in their abdominal cavity.