title: Fish reproductive guilds downstream of dams.
abstract: Fish reproductive guilds were used to evaluate the responses of species with different reproductive strategies during two different periods of post-dam construction. The data used for the comparisons were collected in the upper Paraná River floodplain (Brazil), downstream of the Porto Primavera dam, 2 and 10 years after impoundment. The abundance (catch per unit effort, CPUE), species richness, evenness and structure of communities, all within reproductive guilds, were used to test the hypothesis that these metrics vary spatially and temporally. The influence of damming on species structure and the diversity of fish reproductive guilds varied spatiotemporally, and species with opportunistic reproductive strategies tended to be less affected. Conversely, long-distance migratory species responded more markedly to spatiotemporal variations, indicating that the ecosystem dynamics exert greater effects on populations of these species. Thus, the effects of a dam, even if attenuated, may extend over several years, especially downstream. This finding emphasizes the importance of maintaining large undammed tributaries downstream of reservoirs.
authors.affiliation: Postgraduate Programme in Ecology of Continental Aquatic Environments, Department of Biology, State University of Maringá, 5790 Colombo Avenue, Maringá, PR 87020-900, Brazil.
authors.forename: L P
authors.initials: LP
authors.lastname: Vasconcelos
authors.forename: D C
authors.initials: DC
authors.lastname: Alves
authors.forename: L C
authors.initials: LC
authors.lastname: Gomes
mesh_terms: D000818:Animals; D058448:Biota; D001938:Brazil; D017753:Ecosystem; D005399:Fishes / Q000145:classification* / Q000502:physiology; D012098:Reproduction; D045483:Rivers; D062211:Spatio-Temporal Analysis
keywords: allochthonous species; freshwater; hydropower; ichthyic diversity; invasion