Environmental conditions in river segments intercepted by culverts

The conservation and maintenance of the quality of the rheophilic environment are directly related to knowledge of the physical and chemical characteristics and structural patterns of these systems, especially in streams. Long stretches of small water bodies are highly altered by the construction of highways and roads, which tend to modify their natural characteristics, affecting the environmental quality. This study describes vegetation and morphogeometric parameters of streams with culverts along their courses, reporting spatial differences in environmental characteristics (vegetation, morphogeometric, physical, and chemical) between sampling points upstream and downstream of the culvert. Specifically, we evaluated the width, depth, riparian vegetation, substrate background, and physical and chemical properties of the water, to identify possible differences between the sections above and below (upstream and downstream) of the culvert. The rapid assessment protocol (RAP) was applied to stretches of 200 meters upstream and downstream of culverts in two Neotropical streams, between the months of November 2009 and October 2010. The vegetation and morphogeometric attributes differed between the portions upstream and downstream of the culverts, the latter because of the impoundment effect of these structures. The upstream section becomes flooded, is often shallow, and directly influences the movement of sediment. The physical and chemical variables of the water showed no spatial variation.(Condições ambientais de segmentos fluviais interceptados por bueiros). A conservação e a manutenção da qualidade ambiental do ambiente reofílico está diretamente relacionada ao conhecimento de características físicas e químicas e dos padrões estruturais destes sistemas, especialmente em riachos. Longos trechos de pequenos corpos aquáticos são altamente alterados pela construção de rodovias e estradas e tende a modificar as suas características naturais, interferindo na qualidade ambiental. Neste sentido, o objetivo deste estudo foi descrever parâmetros fito-morfogeométricos de riachos com bueiros em seu curso longitudinal, reportando diferenças espaciais nas características ambientais (fito-morfogeométricos e físico-químicas) entre os pontos amostrados (montante e jusante do bueiro). Especificamente, avaliamos a largura, a profundidade, vegetação ripária, substrato de fundo e atributos físicos e químicos da água, verificando as possíveis divergências entre os trechos de acima e abaixo (montante e jusante) do bueiro. Para isso, o protocolo de avaliação rápida (PAR) foi aplicado em trechos de 200 metros a montante, bem como a jusante de bueiros em dois riachos neotropicais entre os meses de novembro de 2009 e outubro de 2010. Verificou-se que os atributos fito-morfogeométricos diferem entre os trechos de montante e jusante, pois o bueiro tem efeito de represamento. Esse fato transforma o trecho a montante em ambiente alagado, muitas vezes rasos e influenciando diretamente o movimento de sedimentos. As variáveis físicas e químicas da água não apresentaram variação espacial

Espécies de peixes ameaçadas de extinção no Parque Nacional do Iguaçu

Avaliamos a ocorrência e a distribuição de espécies de peixes ameaçadas de extinção em uma das 326 unidades de conservação (UC) federais brasileiras, o Parque Nacional (PARNA) do Iguaçu. As coletas foram realizadas mensalmente, no período de outubro de 2010 a setembro de 2014, no trecho do rio Iguaçu entre a jusante das Cataratas do Iguaçu (na foz com o rio Paraná) e a montante das Cataratas do Iguaçu. Foram coletados 549 peixes pertencentes a nove espécies ameaçadas: quatro categorizadas como Em Perigo (EN): (Brycon orbignyanus, Steindachneridion scriptum, Gymnogeophagus setequedas e Steindachneridion melanodermatum); quatro categorizadas como Vulneráveis (VU): (Pseudopimelodus mangurus, Rhinelepis strigosa, Salminus brasiliensis e Zungaru jahu); e uma espécie categorizada como Quase Ameaçada (NT) (Pseudoplatystoma corruscans). Foi registrada maior abundância de peixes nos locais amostrados dentro do PARNA do Iguaçu. Das espécies amostradas a jusante das Cataratas do Iguaçu, duas foram constantes, duas acessórias e três acidentais. O trecho a jusante e montante das Cataratas do Iguaçu demonstraram ser de grande importância para a conservação dessas espécies. Os resultados encontrados neste estudo poderão auxiliar na revisão futura das listas nacional e estadual de espécies de peixes ameaçadas e subsidiar a elaboração de estratégias de manejo e conservação para essas espécies, tanto dentro como fora dos limites do PARNA do Iguaçu

Session B9: Influence of Biometric Parameters, Flow Condition and Water Temperature on Iberian Fish Sprinting Behavior: Volitionally Swimming Performance

Abstract: Knowing the swimming ability of fish is important to detect movement limitations through hydraulic structures: fish passes weirs and slots, gauging stations, culverts, bridges foundations and other. All these obstacles are collectively referred to velocity barriers . Fish behavior will determine the passage of these structures through combination of fish swimming performance and motivation. Once the fish decides to enter the barrier, must swim faster than the speed of the flow to advance. Thus, the swimming performance depends on the fish speed and fatigue time. To estimate these values, we experimented in an open channel flow with fish samples of different size, swimming volitionally against several high-velocity flows and water temperature range. The movement of fish was controlled by PIT telemetry systems and video record. The information obtained (fish speed, ascend time and distance traveled) was processed using survival analysis techniques and the results can be applied to practical problem solving velocity barriers. We have worked with two species of Iberian fish: Iberian barbel (Luciobarbus bocagei) and Northern straight-mouth nase (Pseudochondrostoma duriense). The biometrics parameters, flow velocity and water temperature have a significant influence in fish behavior. Endurance and swimming ability of these species do not differ greatly between them and is much higher than the values which are obtained using other methods as respirometers. The results challenge established fish passage guidelines, suggesting that in some cases these species are capable of passing much higher velocities than was previously believed

Bidirectional connectivity in fishways: A mitigation for impacts on fish migration of small hydropower facilities

Producción Científica1.Most freshwater fish need to move freely through rivers to complete their lifecycles. Thus, river barriers (e.g. dams, culverts and gauging stations) may delay,hinder or even block their longitudinal movements, affecting fish conservation.The most widespread solution to allow upstream fish migration are fishways,whereas downstream migration is basically facilitated through spillways, turbinesor specific solutions such as bypass systems.2. So far, studies and scientific discussions concerning bidirectional movementsthrough fishways are scarce and focused on large dams and reservoirs, mainlywith large migratory species such as salmonids, rather than smaller facilities andlesser known species.3. This study investigated bidirectional movements through a small run-of-the-riverhydropower plant with a pool-and-orifice type fishway, using the Iberian barbel(Luciobarbus bocagei), a potamodromous cyprinid, as the target species. Passiveintegrated transponder and radio tracking data were collected over 4 years andcombined to characterize upstream and downstream movements. The studyfocused primarily on fish movements through the fishway, but also estimated themultiple associated routes of passage.4. The results show diverse fish movements with inter- and intra-annual variability,with several individuals performing bidirectional movements and even some fishreturning over the years.5. The documented movements and observations indicate that fishways can serveas an effective bidirectional migration corridor for fish, potentially enhancing theconservation efforts for potamodromous species. This study supports thedecision to use fishways as an overall mitigation tool to reduce the impact ofsmall hydropower facilities on fish.European Union’s Horizon 2020 research and innovation program. grant agreement no.727830European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie grant agreement no.10103202

Two-way migration of a potamodromous cyprinid in a small hydropower plant with a pool type fishway

Producción CientíficaMost freshwater fish need to move freely through rivers to complete their life cycles. Thus, river barriers that hinder or block their longitudinal movement (e.g., dams, culverts, gauging stations), directly affect their reproductive, feeding, and habitat routes. A holistic solution to these barriers would need to allow directed, undistracted, and bidirectional fish migration between different habitats; that is to say, it would need to allow two-way migration. The most extended solution that would allow upstream fish migration is a fishway. However, for downstream migration fish have alternate routes such as spillways, turbines, or bypasses. Studies and discussions about two-way migration and bidirectional movement through a fishway have been focused on large dams and reservoirs; thus, there is a lack of available data on other environments, less popular species, or smaller dams and weirs. In this sense, it is possible to hypothesize that a fishway, especially in a smaller facility, could enhance two-way migration by allowing bidirectional movement. Therefore, as a first step to analyzing the possibility, we studied longitudinal connectivity (two-way migration and bidirectional movements) through a small run-of-river hydropower plant (HPP) with a step-pool type fishway, a common and representative configuration of several small HPPs around the world. A potamodromous cyprinid—the Iberian barbel (Luciobarbus bocagei)—was selected as the target species. In this study, radio and PIT tracking data were collected for four different years and combined to characterize movement in the full system: fishway, turbines/spillways, and the river reach downstream (up to 3 km) and upstream (up to 4 km) from the HPP. The results demonstrated the existence of several types of movement with inter-annual and intra-annual variability. Several fish even returned over the years. This suggests that, in this type of HPP facility, a fishway can provide bidirectional connectivity and two-way migration, thus ensuring that a great proportion of fish complete their life cycles.European Union’s H2020 - (grant 727830, FIThydro