Os Sistemas para a Transposição de Peixes Neotropicais são, ainda, temas multidisciplinares polêmicos envolvendo cultura ambiental, engenharia, biologia, ecologia, política e economia. Nesse universo de interesses, o econômico diverge do ambiental, principalmente no escopo dos investimentos corporativos em energia hídrica, nos quais a busca de lucros suplanta o compromisso ambiental, deixando o ônus à sociedade e irrelevando o bem renovável dos peixes nos ecossistemas aquáticos. Há um grande interesse corporativo nacional para mistificar e irrelevar as estruturas para passagens de peixes em barramentos de modo à desjustificá-las como alternativa de mitigação de impactos e assim não expandi-las, tornando-as não obrigatórias principalmente em empreendimentos existentes, em que pese às questões ictiológicas abertas e não esclarecidas que deveriam estar em grau de consistência e confiança mais desenvolvidas. Os Estudos de Impactos Ambientais e os relicenciamentos dos barramentos são os instrumentos para disciplinar os STP’s, mas deixam a desejar quando os empreendedores ou investidores são também os agentes que financiam os estudos. As agências licenciadoras contam com uns corpos técnicos inexperientes e susceptíveis a informações parciais e com forte empenho político e econômico. A concepção, projeto, manuseio de vazões, níveis, velocidades, potência do escoamento são de natureza hidráulica para as quais os engenheiros, atendendo as premissas biológicas dos peixes, são os agentes indicados para o tratamento dos sistemas para a transposição de peixes em barragens. Neste trabalho há as propostas para STP’s nacionais baseadas em de estudos de similitude tridimensional; a apresentação de recomendações e critérios baseados na experiência nacional além da proposta experimental de criadouros artificiais em reservatórios e afluentes simulando-se os baixios e lagoas marginais. Para que as informações contidas neste trabalho não sejam reproduzidas erroneamente: as dimensões do STP devem ser concebidas em função das espécies a serem transportadas, que variam segundo as variáveis ambientais locais. O projeto de um STP não pode ser padronizado, pois implicará em erros. Padronizar um STP é reduzir a técnica e a ciência a um padrão primário, tipo “Manual de Bolso”, o que não atenderia aos peixes, fadando a concepção ao insucesso. / The theme “Systems for Neo-tropical Fishes Transposition” is a multidisciplinary subject: it encompasses the fields of engineering, biology, ecology, politics, economy and environmental culture. It is also a polemic subject: in a broad range of interests, most of the time the economical overtake the environmental ones. This is especially true when corporative investments in hydroelectric energy are under consideration, where seek for profits supersedes the environmental commitments, leaving to the community the liability of endangering fish species’ renewal in aquatic ecosystems. In fact, there is a strong corporative interest, in the national context, to obstacle fish passage devices, not only for new dam structures, but also for the existing ones. Among the local entrepreneurs there is a tendency to mystify and underestimate fish passage structures, as a way to disqualify them as effective mitigative measures. The development of a “fish passages culture” in the country becomes even more difficult. Additionally, there are several non-clarified questions related to neo-tropical fish species; those issues should already be in a more developed consistency and soundness stage. Environmental Impact Assessments and existing dams Re-licensing Processes should play a disciplinary role for fish passage structures, but they usually fail when the investors and/or entrepreneurs are the ones who financially support those studies. Even worse, licensing agencies’ technical staffs frequently lack on reliable information and let themselves be guided by political and economical interests. The treatment of discharges, water levels, velocities, energy of flow, dimensions and layout or, in a broader sense, the conception and design of fish passage structures, should only be carried out by specialist engineers, with the invaluable supervision of biologists. The objective of this Thesis is the proposition of fish passage structures adapted to the conditions of Brazilian rivers and following the results of studies with reduced scale tri-dimensional models. Also some recommendations and criteria are presented, supported by the feedback from nationwide experience. Finally, a proposition is presented for the experimental implementation of artificial breeding farms along reservoirs and tributaries, where the conditions of swamps and peripheral ponds could be reproduced. The dimensions of the STP must be function of the species to be transponding, of this form its conception cannot be standardized, therefore it will imply in errors. To standardize a STP is to reduce the technique and science to a secundarista standard, Manual of Pocket, what it would not take care of to the fish, predestinateing the conception to failure.

Steelhead and rainbow trout are common names for marine-migratory (anadromous) and freshwater-resident forms of Oncorhynchus mykiss, a partially migratory salmonid fish. Anadromous and resident forms are sympatric and can produce offspring with a life history different from their own (i.e., steelhead parents can produce rainbow trout offspring and vice versa). The expression of these alternative life histories is a plastic response to individual patterns of energy acquisition, assimilation, and allocation during juvenile life stages. Individual performance during early stream life is of particular interest because of potential carry-over effects on subsequent growth and developmental trajectories. In a series of experiments in laboratory streams, I determined the influence of individual variation in energy metabolism on behavior, growth, and life-history expression in O. mykiss. Individual variation in energy metabolism was a strong predictor of feeding territory acquisition by juvenile fish during the transition from dependence on maternal provisioning of egg yolk reserves to independent feeding. Feeding territory acquisition was positively associated with standard metabolic rate (SMR) under conditions of an abundant and predictable food supply. When the density of intraspecific competitors was manipulated, the association between SMR and territory acquisition was strongest at intermediate stocking densities, moderate at the highest stocking densities, and weakest at the lowest stocking densities. However, reducing the spatial predictability of food resources within streams reversed the influence of SMR on competitive outcomes. These experiments determined that variation in ecological conditions during early life stages imposes different selection regimes on juvenile O. mykiss and results in physiological divergence among cohorts. Subsequent rearing experiments determined that behavioral dominance influences rates of anadromy and freshwater maturation, most likely through the association between SMR and territory acquisition. In addition to the effects of behavioral dominance, I observed a significant influence of sex, rearing temperature, and individual growth trajectories on the expression of anadromy and freshwater maturation. Partially migratory populations of O. mykiss maintain an exceptionally diverse portfolio of life-history strategies. Results from this work lend insight into a suite of behavioral and physiological processes influencing individual life histories. / Graduation date: 2013

Migration occurs among many animal species for the purpose of, among other things, finding food or to reproduce. Spawning migration is a form of migration that occurs among many fish species where they move to another site for reproduction. The movement can be obstructed by migration barriers like road culverts. Barriers to migration pose one of the greatest threats to biodiversity and ecosystem functions in freshwater. They impair the connectivity of watercourses and may prevent fish from improving reproductive success or completing their life histories altogether. There are both benefits and costs with migration, benefits such as increased survival for the adults and offspring, and costs such as increased energy consumption and increased mortality. The costs are often dependent on the morphological traits of the individual, like body shape and size. In this study, the spawning migration of two species of fish of the family Cyprinidae, ide (Leuciscus idus) and roach (Rutilus rutilus) was investigated. Few studies have been made on ide or on roach compared to other cyprinids and salmonids. This study might therefore enhance the overall knowledge of these two species. The overall aims of this project are to study and compare phenotypic correlates of spawning migration behaviour of ide and roach. The field studies were performed in Oknebäcken, Mönsterås (SE632310-152985), Sweden in March and April 2020. To describe the watercourse and define the location and characteristics of different potential migration barriers, a simplified biotope mapping method was used. The fish were caught in a hoop net and then measured, weighted, sexed, and injected with passive integrated transponder using the bevel down method. In order to register in stream movement of fish, reading stations with antennas were placed, at two locations upstream from the marking station and one downstream at the estuary. The sex ratio differed from the expected 1:1 with a majority of females for both species. This might be a result of fluctuations in survival of spawn coupled with different age-at-maturity between sexes. We found that individuals that arrived early to the stream were larger for both study species, as other studies also reported. Also, male ide was both larger and arrived before female ide. There might be an energy cost associated with early arrival to the stream and therefore, larger individuals arrive first. For roach, there was no difference in arrival time between the sexes although female roach were larger. There was no difference in the time spent in the stream between the species. For ide, females stayed for a longer period of time in the stream than males. However, the opposite was true for roach. This may be because male roach might benefit from more fertilization events when staying longer. There might therefore be a trade-off between the energy cost in staying in the stream and the increased fitness advantage in fertilization events. We found no correlation between any of the morphological traits and migration distance. However, since very few individuals were registered at the upstream reading stations, there might be an effect of migration barriers on the spawning migration. The mortality after spawning was higher for roach than for ide. For ide, a larger proportion of females than males died. For roach, individuals that arrived early was classified as alive to a greater extent than those who arrived late. Both similarities and differences between the species were discovered in this study which concludes that even closely related species might differ substantially from each other.

The Swedish national plan for reapproval of hydropower describes that hydropower plants (HPPs) are required to be reassessed to ensure that modern environmental conditions are set for the permits. Since dams and HPPs create barriers for migrating fish and consequently disfavor biological diversity, one consequence of the national plan is that fishways are being constructed. This, in combination with an old, unfinished approval procedure from the 1960’s, resulted in the construction of three up- and downstream fishways in Mora municipality, at the HPPs in Spjutmo, Blyberg and Väsa. To fulfill requirements in regard to the fishway’s incline and safety, but at the same time minimize the need of space, the fishways have new, innovative and not yet tested design features. One of these features is the “parking garage” layout of the upstream fishway. Despite these features, the fishways take up a large amount of space and thus require large amounts of blasting, excavation and materials such as concrete and steel parts. These are climate impact influence intensive procedures and materials, but the construction has so far not been evaluated from a climate impact perspective. This, in combination with a lack of studies on the climate impact of fishways, has resulted in this project.The aim of this project was to examine the climate impact caused by the fishways in Spjutmo and Blyberg, to identify what affects the total climate impact as well as providing measures that could reduce the climate impact for future similar fishways. To provide an extensive overview of the climate impact that the fishways cause during their entire lifetime, the method life cycle analysis (LCA) was used. The construction of the fishways at Väsa HPP starts later than for Spjutmo and Blyberg, and therefore Väsa is excluded from the scope due to the lack of required information.The fishways in Spjutmo and Blyberg have the same design features, but the material consumptions differ due to their differences in head. Spjutmo’s head is 21,4 meter and Blyberg’s is 11 meter. A larger head generally results in a longer fishway which in turn results in a more material consuming construction. This resulted in the total life cycle climate impact being twice as big for Spjutmo as for Blyberg, 2 807 tonne CO2-eq respectively 1 361 tonne CO2-eq. The resource extraction is the LCA- phase that contributes the most. Concrete and its reinforcement have the biggest share of that impact, followed by mechanical parts and other steel products, road construction process in Spjutmo and the excavation process in Blyberg. Based on this result, it can be concluded that the materials and components contribute more to the fishways’ total climate impact, rather than processes. Roughly 80 % of the total climate impact origins from the upstream fishway, while the rest either stems from the downstream fishway or others. Sensitivity analyses include the climate impact caused by the fishways using some water that otherwise could have been used to generate electricity from, and the result indicates that all examined alternative energy sources would result in larger climate impact compared to if the electricity was generated by hydropower.One of the result’s uncertainties is that the fishways were under construction while this project was performed. Therefore some assumptions was made to compensate for lack of data. For example, the future electricity consumption was scaled up based off the then used electricity data. However, even if some amounts of required materials and processes changed as time went by, the changes did not make a significant difference from the bigger perspective. Sensitivity analyses that examined the climate impact of a delay in the construction also showed that the processes that are most likely to continue turned out to have a relatively small climate impact. Thus, this issue might not be as problematic as initially thought.Although the result is presented in total values, the result is also provided per a functional unit (FU) level in accordance with traditional LCA methodology. This was to facilitate a comparison for future LCAs on other fishways. The FU in this project was decided to be “One meter head for a technical, stationary, up- and downstream fishway in connection to a medium or large run-of-river hydropower plant in a cold tempered climate zone”. For future studies, LCAs on different types of fishways using the proposed FU is recommended.

This dissertation thesis focuses on several aspects of fish ecology in reservoirs and the methodology of their sampling. It is divided to three parts. The first part focuses on the dynamics of fish distribution throughout the seasons and between day and night. The second part deals with the efficiency and the selectivity of the beach seine net, trawl and purse seine net. The third part describes the long-term development of fish populations in the Římov Reservoir.

The evolution and maintenance of multiple phenotypes within populations is an interesting evolutionary and ecological question, and is becoming increasingly important for the restoration and conservation of partially migratory species. In particular, why individuals adopt a particular phenotype has been the focus of numerous research efforts. In the partially migratory species Oncorhynchys mykiss (commonly known as steelhead and rainbow trout), I found that sex plays a strong role in whether an individual adopts an anadromous or resident life history. I observed a higher frequency of females adopting the anadromous tactic throughout the species range, and I attributed this to the relationship between body size and reproductive success in females that is not present in males. I did not observe differences in female bias along gradients of latitude or migration distance, and I hypothesize that while the frequency of tactics among populations may change along these gradients, either the change is equal between males and females, or an interaction of latitude and migration distance may control changes. I did not observe a corresponding male bias in the one resident population I sampled, and suggest that this is the result of a high frequency of residents in that population. I propose that sex ratios could be a valuable metric for measuring frequency of life-history tactics in populations and could facilitate the investigation into the controls of life-history tactics across broad scales. / Graduation date: 2013