caa a22 4500 445893168 CHVBK 20180317145623.0 cr unu---uuuuu 170323e20111001xx s 000 0 eng 10.1007/s10750-011-0787-0 doi (NATIONALLICENCE)springer-10.1007/s10750-011-0787-0 All that goes up must come down? Absence of downstream passage through a fish ladder in a large Amazonian river [Elektronische Daten] [Carlos Agostinho, Fernando Pelicice, Elineide Marques, Anderson Soares, Deusimar de Almeida] Millions of fish ascend through fishways in South America every year, but there is no evidence that downstream passage is occurring in large dams. Based on this concern, this study monitored the fish ladder at Lajeado Dam, Tocantins River, a large Amazonian tributary. To investigate the extent of downstream movements through the fishway, ascending and descending movements were quantified between November 2007 and October 2008. Monitoring showed that the ladder is restrictive to many species in both directions, but downstream passage was much more limited: almost all fish captured in the ladder (99.5%) were ascending the facility. Consequently, the numerical ratio between ascending and descending fish (ind./m2) showed high positive values throughout the year (1508:1 on average); migratory species showed higher ratios. All results showed that downstream passage through the ladder is very limited, and that the facility allows only one-way movements (i.e., upstream). This is the first empirical evidence showing that a ladder is critically deficient for downstream passage of fishes in South America. Springer Science+Business Media B.V., 2011 Conservation nationallicence Fish ladder nationallicence Management nationallicence Migratory fish nationallicence South America nationallicence Agostinho Carlos Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut Pelicice Fernando Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut Marques Elineide Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut Soares Anderson Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut de Almeida Deusimar Investco S.A., Miracema do Tocantins, TO, Brazil aut Hydrobiologia Springer Netherlands 675/1(2011-10-01), 1-12 0018-8158 675:1<1 2011 675 10750 https://doi.org/10.1007/s10750-011-0787-0 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10750-011-0787-0 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Agostinho Carlos Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut NATIONALLICENCE 700 1- Pelicice Fernando Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut NATIONALLICENCE 700 1- Marques Elineide Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut NATIONALLICENCE 700 1- Soares Anderson Núcleo de Estudos Ambientais (Neamb), Universidade Federal do Tocantins, Rua 3, Quadra 17, Jardim dos Ipês, 77500-000, Porto Nacional, TO, Brazil aut NATIONALLICENCE 700 1- de Almeida Deusimar Investco S.A., Miracema do Tocantins, TO, Brazil aut NATIONALLICENCE 773 0- Hydrobiologia Springer Netherlands 675/1(2011-10-01), 1-12 0018-8158 675:1<1 2011 675 10750 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer