Are there successful fish passes? Lessons from South America. Paulo Santos Pompeu Federal University of Lavras

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1 Are there successful fish passes? Lessons from South America Paulo Santos Pompeu Federal University of Lavras

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5 Is it possible to build a successful fish pass? When it is not possible? Could we know when it is definitively not possible, and when it is possible?

6 Fisheries management in South American reservoirs has been based on stocking, fisheries harvest limits, and construction of fish passes. The low fishery yield, the precarious conservation status of native population in southern and southeastern Brazil reservoirs, and the significant reduction of migratory species clearly indicate that this strategy is not satisfactory.

7 Spawning areas Adults Feeding areas Eggs and larvae Nurseries (Floodplains) Juveniles General movements of the migratory fishes of Paraná and São Francisco River basins (Adapted from Godinho & Pompeu, 2003).

8 The objectives of a fish passage Upstream passage alone is not indicative of population recruitment and conservation of stocks, because fish may ascend the pass but recruitment may not occur. Therefore, the objectives of a fish pass should be directly related to the spatial distribution of critical habitats, such as reproduction sites and nursery areas downstream or upstream.

9 Because the populations may become self sustainable in the long-term in both regions, these passes would become questionable or justified only for the maintenance of the genetic flow between the populations. Reduced success of downstream movements of fish could result in decreased downstream fish stocks. Nursery areas Reproduction sites Dam of interest

10 Passes operating in these conditions may function as ecologic traps (Pelicice and Agostinho, 2008), because they remove the fish from healthy environments and transport them to sites with no critic habitats. Nursery areas Reproduction sites Dam of interest

11 This is the only case study where maintenance of connectivity between areas upstream and downstream is crucial for maintaining migratory species populations. If the descendent migration does not happen, the pass loses its value to recruitment conservation. To avoid this situation, the distribution of critical habitats should be thoroughly evaluated during the inventory of the hydroelectric potential of the reach. Nursery areas Reproduction sites Dam of interest

12 Passes aiming to maintain recruitment are irrational in this situation if they do not reconnect critical fish habitats in the river by incorporating passes at all the dams. Nursery areas Reproduction sites Dam of interest

13 Back to the questions... Is it possible to build a successful fish pass? When it is not possible? Could we know when it is definitively not possible, and when it is possible?

14 To implement a functional upstream pass would be the first step..but Table 1. Some functioning aspects evaluated in fish passages installed in South America, such as selectivity (% of species not registered in the fish way, based on fish surveys in the region), selectivity along the passage (% of species passed to the reservoir or that reached upper parts of the passage, based on the number of species registered in the fish way), upstream passage efficiency (% of fish passed upstream, based on the number of fish recorded below the dam), and downstream passage (qualitative/quantitative indications of downstream passage). Aspects that were not investigated are marked with -. Hydropower dam (height) Canoa Quebrada (25 m) Peixe Angical (39 m) Lageado (37 m) Igarapé (6 m) Risoleta Neves (49 m) Santa Clara (60 m) Salto Moraes (11 m) Funil (45 m) Igarapava (18 m) Canoas I (29 m) Canoas II (25 m) Porto Primavera (22 m) Itaipú (196 m) Itaipú (196 m) Yaceretá (21 m) Salto Grande (30 m) Fish passage type (length) (400 m) (575 m) (874 m) (?) Trap and Truck Trap and Truck (78 m) (228 m) (520 m) (155 m) Channel (10 km) Basin Reservoir area km 2 Local situation (Fig. 1) Amazon 11.7? Tocantins 294 A Tocantins 630 A São Francisco < 1 A Doce 3.5 A Mucuri 7.5 D Paraná -? Fish lift Paraná 33.5 E (282 m) (210 m) Paraná 36 B Paraná 30 B Paraná 22 F Paraná 2,250 B Paraná 1,350 A Paraná 1,350 A Fish lift Paraná 1,600? Fish locks Uruguay 800? Selectivity (dominance?) - 59% 37% 28% 54% 59% 10% 32% 25% Selectivity along the passage Total Migratory fauna - - Local Situation = see Figure 1 for code explanation (A-F). Categorization is based on present author s judgment. Dominance = a few species (3-5) summing more than 70% of captures.? (?) 71% 3% 17% 8% 44% 21% Upstream passage Downstream passage efficiency Total Migratory Adults Eggs/Larvae fauna % 38% Unlikely 48% 53% - - Unlikely Unlikely Probably high Probably high - 22% No Reproduction areas absent Reproduction areas absent 15% 11% % 41% % 0.68% References Junho et al., 2007 Freitas et al., 2009 Agostinho et al., 2007b; 2007c % - - Alves, ,5% 0,8% 3.1% 7.0% Very reduced Possible 98% Unlikely Probably high Probably high No Reproduction areas absent Braga et al., 2007 Pompeu, 2005; Pompeu et al., 2007 Godinho et al., 1991 Pereira & Pompeu, 2010; Suzuki, 2009 Bizzoto et al., 2009; Casali et al., 2010 Brito & Sirol, 2005; Hoffman et al., Brito 2005; & Lopes Sirol, et 2005; Hoffman et al., 2005; Lopes et al., 2007 Makrakis et al., 2007 Fernandez et al., 2004 Makrakis et al., 2007; Okada et al., 2005 Oldani & Baigun, 2003; Oldani et al., 2007 Oldani et al., 2007

15 To implement a functional upstream pass would be the first step..but The success will depend mainly on: The availability of critical habitats...

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17 To implement a functional upstream pass would be the first step..but The success will depend mainly on: The feasibility of downstream passage... Reservoir area (km 2 ) p = r 2 = Known limit for dowstream passage of eggs and larvae Dam height (m) Reservoirs area in big rivers in Brazil

18 Why is difficult to deal with downstream migration through reservoirs? Dam Reservoir Characteristics of the barrier Vertical Horizontal Abrupt Gradient Structural Hydraulic/Limnological Relation to fish biology Physical Behavioral Main movements prevented Upstream reproductive migration of adults Upstream dispersion of juveniles and adults Downstream migration of adults, eggs and larvae Selectivity High to upstream movements High to downstream movements Unknown to downstream movements Probably low to upstream movements Technical solution Available Unavailable s, lifts, canals Effectiveness of solution Medium to low Unavailable

19 Back to the South America experience... Table 1. Some functioning aspects evaluated in fish passages installed in South America, such as selectivity (% of species not registered in the fish way, based on fish surveys in the region), selectivity along the passage (% of species passed to the reservoir or that reached upper parts of the passage, based on the number of species registered in the fish way), upstream passage efficiency (% of fish passed upstream, based on the number of fish recorded below the dam), and downstream passage (qualitative/quantitative indications of downstream passage). Aspects that were not investigated are marked with -. Hydropower dam (height) Canoa Quebrada (25 m) Peixe Angical (39 m) Lageado (37 m) Igarapé (6 m) Risoleta Neves (49 m) Santa Clara (60 m) Salto Moraes (11 m) Funil (45 m) Igarapava (18 m) Canoas I (29 m) Canoas II (25 m) Porto Primavera (22 m) Itaipú (196 m) Itaipú (196 m) Yaceretá (21 m) Salto Grande (30 m) Fish passage type (length) (400 m) (575 m) (874 m) (?) Trap and Truck Trap and Truck (78 m) (228 m) (520 m) (155 m) Channel (10 km) Basin Reservoir area km 2 Local situation (Fig. 1) Amazon 11.7? Tocantins 294 A Tocantins 630 A São Francisco < 1 A Doce 3.5 A Mucuri 7.5 D Paraná -? Fish lift Paraná 33.5 E (282 m) (210 m) Paraná 36 B Paraná 30 B Paraná 22 F Paraná 2,250 B Paraná 1,350 A Paraná 1,350 A Fish lift Paraná 1,600? Fish locks Uruguay 800? Selectivity (dominance?) - 59% 37% 28% 54% 59% 10% 32% 25% Selectivity along the passage Total Migratory fauna - - Local Situation = see Figure 1 for code explanation (A-F). Categorization is based on present author s judgment. Dominance = a few species (3-5) summing more than 70% of captures.? (?) 71% 3% 17% 8% 44% 21% Upstream passage Downstream passage efficiency Total Migratory Adults Eggs/Larvae fauna % 38% Unlikely 48% 53% - - Unlikely Unlikely Probably high Probably high - 22% No Reproduction areas absent Reproduction areas absent 15% 11% % 41% % 0.68% References Junho et al., 2007 Freitas et al., 2009 Agostinho et al., 2007b; 2007c % - - Alves, ,5% 0,8% 3.1% 7.0% Very reduced Possible 98% Unlikely Probably high Probably high No Reproduction areas absent Braga et al., 2007 Pompeu, 2005; Pompeu et al., 2007 Godinho et al., 1991 Pereira & Pompeu, 2010; Suzuki, 2009 Bizzoto et al., 2009; Casali et al., 2010 Brito & Sirol, 2005; Hoffman et al., Brito 2005; & Lopes Sirol, et 2005; Hoffman et al., 2005; Lopes et al., 2007 Makrakis et al., 2007 Fernandez et al., 2004 Makrakis et al., 2007; Okada et al., 2005 Oldani & Baigun, 2003; Oldani et al., 2007 Oldani et al., 2007 Where it was possible to implement an effective passage? Where it was not? What were the lessons? Did it help guide future dams?

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23 Salminus franciscanus km km

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25 Minas Gerais State

26 Conservation status

27 Socio-economic development

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29 Main messages: In Brazil, fisheries based on migratory species is related to free flowing river, not to successful fish passage; The environment impact assessment will depend on the location of the critical habitats, and on the size of the reservoir.

30 THANK YOU! Paulo Pompeu