Tática reprodutiva e estrutura da população de Cichla monoculus Spix & Agassiz, 1831 (Perciformes, Cichlidae) em ambientes com diferentes regimes hidrológicos.

Detalhes bibliográficos
Ano de defesa: 2005
Autor(a) principal: Espinola, Luis Alberto
Orientador(a): Não Informado pela instituição
Banca de defesa: Não Informado pela instituição
Tipo de documento: Dissertação
Tipo de acesso: Acesso aberto
Idioma: por
Instituição de defesa: Universidade Estadual de Maringá
Brasil
Programa de Pós-Graduação em Ecologia de Ambientes Aquáticos Continentais
UEM
Maringá
Departamento de Biologia
Programa de Pós-Graduação: Não Informado pela instituição
Departamento: Não Informado pela instituição
País: Não Informado pela instituição
Palavras-chave em Português:
Link de acesso: http://repositorio.uem.br:8080/jspui/handle/1/4916
Resumo: This study assumed that some species are able to change the reproductive tactic depending on currently environmental conditions. The tested hypothesis is that the peacock bass Cichla monoculus, an introduced species of Amazonian region, presents a differential reproductive tactic that depends on the variation of the hydrometric level on the upper Paraná River floodplain and Corumbá Reservoir. The hydrological analysis showed that the level on the floodplain was very irregular compared to the level on the reservoir, presenting often potamophases. Limnophases were less frequent and of long duration. Because of the short retention time, hydrometric level variations on reservoir were of less than 9 cm above and below the overflow level, with the same number of potamophases and limnophases, both of them of similar duration. Either in the floodplain as in the reservoir, abundance peaks of juveniles occurred on potamophases. In the floodplain, these peaks were associated to sharp increase of short duration of the hydrometric level, especially in February 2000 and March 2003. In the reservoir, the occurrence of juveniles was registered practically in all samplings, with two peaks in April and December 1998, corresponding to the rainfall period. In both systems, juvenile abundance was positively correlated with the hydrometric level. It was concluded that C. monoculus changes its reproductive tactic responding to variations of hydrometric level and environmental seasonality.