SciELO - Scientific Electronic Library Online

 
vol.29 número1Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern ChinaAnatomy of the digestive tube of sea turtles (Reptilia: Testudines) índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados

Journal

Artigo

Indicadores

Links relacionados

Compartilhar


Zoologia (Curitiba)

versão impressa ISSN 1984-4670

Resumo

HAUSER, Marília  e  BENEDITO, Evanilde. Species of the Hoplias aff malabaricus complex (Characiformes: Erythrinidae): An investigation of coexistence in a Neotropical floodplain. Zoologia (Curitiba) [online]. 2012, vol.29, n.1, pp.59-69. ISSN 1984-4670.  http://dx.doi.org/10.1590/S1984-46702012000100007.

This study assessed the coexistence of three species of thraira present in the Upper Paraná River floodplain, using population structure as an investigation tool. The species were designated as: Hoplias sp. 1, introduced after the construction of the Itaipu reservoir, and Hoplias sp. 2 and Hoplias sp. 3, native species that have been identified as Hoplias aff. malabaricus. We tested the hypothesis that those species in fact differ from each other in respect of population abundance, sex ratio, relative frequency of adults and juveniles, length structure and weight-length relationship. Additionally, possible effects of the flood pulse on the first four of these parameters were investigated. Samples were collected quarterly from March 2006 to December 2007 from nine collection sites on the floodplain. Hoplias sp. 1 presented a greater balance of sex ratio and length structures over the seasons, as well as a higher allometric coefficient. The population attributes of Hoplias sp. 2 and Hoplias sp. 3 showed a high responsiveness to hydrological seasonality, indicating that these species exploit available resources in a conspicuous flood period with greater efficiency. These differences, beyond reflecting possible mechanisms that allow closely related species to coexist, indicate the importance of understanding the life strategies adopted by each species which, as part of a complex system, are considered key elements of the aquatic community structure in the region, providing important information for habitat management and biodiversity conservation.

Palavras-chave : Dams; flood pulse; species introduction; structure population; thraira.

        · texto em Inglês     · Inglês ( pdf )

 

Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons