SciELO - Scientific Electronic Library Online

 
vol.77 número4Phytophagy of the predator Podisus nigrispinus (Dallas, 1851) (Hemiptera: Pentatomidae) fed on prey and BrassicaceaeNesting of Morelet’s crocodile, Crocodylus moreletii (Dumeril and Bibron), in Los Tuxtlas, Mexico índice de autoresíndice de materiabúsqueda de artículos
Home Pagelista alfabética de revistas  

Servicios Personalizados

Revista

Articulo

Indicadores

Links relacionados

Compartir


Brazilian Journal of Biology

versión impresa ISSN 1519-6984versión On-line ISSN 1678-4375

Resumen

SCHORK, G.  y  ZANIBONI-FILHO, E.. Structure dynamics of a fish community over ten years of formation in the reservoir of the hydroelectric power plant in upper Uruguay River. Braz. J. Biol. [online]. 2017, vol.77, n.4, pp.710-723.  Epub 25-Mayo-2017. ISSN 1519-6984.  http://dx.doi.org/10.1590/1519-6984.17015.

The objective of this study was to evaluate the structure of the fish assemblage in the ten years following the closing of the lake of the Itá Hydroelectric Power Plant. Seasonal collections were conducted from 2001 to 2010. During this period, 44,834 fish were captured, totaling 3,818.01 kg, among 8 orders, 24 families and 84 species. In general, profound changes were not observed in the fish assemblage in the ten years after the formation of the Itá lake. Few species changed in dominance over time, while many were rare in the environment. The ichthyofauna in the reservoir was dominated by small and medium size opportunist species that conduct short or no migratory movements. Among the most abundant, six species were responsible for more than 50% of the numeric representation: Steindachnerina brevipinna, Astyanax fasciatus, Apareiodon affinis, Hypostomus isbrueckeri, Iheringichthys labrosus and Loricariichthys anus. The increase in the representation of the later species stood out. The biomass was dominated by Steindachneridion scriptum, Prochilodus lineatus, I. laborsus, Schizodon nasutus, Hoplias malabaricus, Acestrorhynchus pantaneiro, Hoplias lacerdae, H. isbrueckeri and L. anus. Despite the presence of large migrators in the region of the reservoir, their vulnerability was revealed by the low numeric abundance and accidental capture. The k-dominance curve of numerical abundance and biomass indicates a moderately disturbed community, in which the representation of small species was also important to the amounts of biomass.

Palabras clave : dam; ichthyofauna; southern Brazil; temporal variation; Itá.

        · resumen en Portugués     · texto en Inglés     · Inglés ( pdf )