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Jost
24.09.2014, 06:47
Fish reproductive guilds downstream of dams
L. P. Vasconcelos, D. C. Alves and L. C. Gomes

Journal of Fish Biology (2014) doi:10.1111/jfb.12501
https://onlinelibrary.wiley.com/doi/10.1111/jfb.12501/abstract?campaign=wolearlyview

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 reproduc-
tive 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."