The Experts below are selected from a list of 13884 Experts worldwide ranked by ideXlab platform
Hugo Marques - One of the best experts on this subject based on the ideXlab platform.
-
importance of reservoir tributaries to spawning of Migratory Fish in the upper parana river
River Research and Applications, 2015Co-Authors: P S Da Silva, Sergio Makrakis, Leandro E. Miranda, Maristela Cavicchioli Makrakis, Lucileine De Assumpcao, S Paula, Joao Henrique Pinheiro Dias, Hugo MarquesAbstract:Regulation of rivers by dams transforms previously lotic reaches above the dam into lentic ones and limits or prevents longitudinal connectivity, which impairs access to suitable habitats for the reproduction of many Migratory Fish species. Frequently, unregulated tributaries can provide important habitat heterogeneity to a regulated river and may mitigate the influence of impoundments on the mainstem river. We evaluated the importance of tributaries to spawning of Migratory Fish species over three spawning seasons, by comparing several abiotic conditions and larval Fish distributions in four rivers that are tributaries to an impounded reach of the Upper Parana River, Brazil. Our study confirmed reproduction of at least 8 long-distance migrators, likely nine, out of a total of 19 occurring in the Upper Parana River. Total larval densities and percentage species composition differed among tributaries, but the differences were not consistent among spawning seasons and unexpectedly were not strongly related to annual differences in temperature and hydrology. We hypothesize that under present conditions, densities of larvae of Migratory species may be better related to efficiency of Fish passage facilities than to temperature and hydrology. Our study indicates that adult Fish are finding suitable habitat for spawning in tributaries, Fish eggs are developing into larvae, and larvae are finding suitable rearing space in lagoons adjacent to the tributaries. Our findings also suggest the need for establishment of protected areas in unregulated and lightly regulated tributaries to preserve essential spawning and nursery habitats. Copyright © 2014 John Wiley & Sons, Ltd.
Mufeed Odeh - One of the best experts on this subject based on the ideXlab platform.
-
swimming performance of upstream migrant Fishes in open channel flow a new approach to predicting passage through velocity barriers
Canadian Journal of Fisheries and Aquatic Sciences, 2004Co-Authors: Alex Haro, Theodore Castrosantos, John Noreika, Mufeed OdehAbstract:The ability to traverse barriers of high-velocity flow limits the distributions of many diadromous and other Migratory Fish species, yet very few data exist that quantify this ability. We provide a detailed analysis of sprint swimming ability of six Migratory Fish species (American shad (Alosa sapidissima), alewife (Alosa pseudoharengus), blueback herring (Alosa aestivalis), striped bass (Morone saxatilis), walleye (Stizostedion vitreum), and white sucker (Catostomus commersoni)) against controlled water velocities of 1.54.5 m·s1 in a large, open-channel flume. Performance was strictly voluntary: no coercive incentives were used to motivate Fish to sprint. We used these data to generate models of maximum distance traversed, taking into account effects of flow velocity, body length, and temperature. Although the maximum distance traversed decreased with increasing velocity, the magnitude of this effect varied among species. Other covariate effects were likewise variable, with divergent effects of tempera...
-
swimming performance of upstream migrant Fishes in open channel flow a new approach to predicting passage through velocity barriers
Canadian Journal of Fisheries and Aquatic Sciences, 2004Co-Authors: Alex Haro, Theodore Castrosantos, John Noreika, Mufeed OdehAbstract:The ability to traverse barriers of high-velocity flow limits the distributions of many diadromous and other Migratory Fish species, yet very few data exist that quantify this ability. We provide a...
-
Evaluation of the Effects of Turbulence on the Behavior of Migratory Fish, 2002 Final Report.
2002Co-Authors: Mufeed OdehAbstract:The fundamental influence of fluid dynamics on aquatic organisms is receiving increasing attention among aquatic ecologists. For example, the importance of turbulence to ocean plankton has long been a subject of investigation (Peters and Redondo 1997). More recently, studies have begun to emerge that explicitly consider the effects of shear and turbulence on freshwater invertebrates (Statzner et al. 1988; Hart et al. 1996) and Fishes (Pavlov et al. 1994, 1995). Hydraulic shear stress and turbulence are interdependent natural hydraulic phenomena that are important to Fish, and consequently it is important to develop an understanding of how Fish sense, react to, and perhaps utilize these phenomena under normal river flows. The appropriate reaction to turbulence may promote movement of Migratory Fish (Coutant 1998) or prevent displacement of resident Fish. It has been suggested that one of the adverse effects of flow regulation by hydroelectric projects is the reduction of normal turbulence, particularly in the headwaters of reservoirs, which can lead to disorientation and slowing of migration (Williams et al. 1996; Coutant et al. 1997; Coutant 1998). On the other hand, greatly elevated levels of shear and turbulence may be injurious to Fish; injuries can range from removal of the mucous layer on the body surface to descaling to torn opercula, popped eyes, and decapitation (Neitzel et al. 2000a,b). Damaging levels of fluid stress, such turbulence, can occur in a variety of circumstances in both natural and man-made environments. This report discusses the effects of shear stress and turbulence on Fish, with an emphasis on potentially damaging levels in man-made environments. It defines these phenomena, describes studies that have been conducted to understand their effects, and identifies gaps in our knowledge. In particular, this report reviews the available information on the levels of turbulence that can occur within hydroelectric power plants, and the associated biological effects. Furthermore, this report describes an experimental apparatus designed to test the effect of turbulence on Fish, and defines its hydraulics. It gives the results of experiments in which three different Fish species were exposed to representative levels of turbulence in the laboratory.
Angelo Antonio Agostinho - One of the best experts on this subject based on the ideXlab platform.
-
TEMPORAL CHANGES IN Migratory Fish BODY SIZE IN A NEOTROPICAL FLOODPLAIN
Oecologia Australis, 2020Co-Authors: Taise Miranda Lopes, Anielly Galego De Oliveira, Luiz Carlos Gomes, Oscar Peláez, Rosa Maria Dias, Rafaela Giacomeu Rauber, Angelo Antonio AgostinhoAbstract:Body size is a trait that results from evolutionary and ecological processes. Body size not only provides information on the physical condition of individuals but also on the shift in community structure across space and time. Here, we aimed to investigate whether the body size of the Migratory Fishes changed over time and to ascertain the abiotic variables explaining these changes; and whether the effect on body size was different between Fish in dammed (Parana River) and undammed (Ivinhema River) rivers. Using a temporal series (1986 - 2018) and linear mixed effects models, we evaluated the effects of the abiotic variables on the standard length of the Fish species from a floodplain system. We found that Fish body size tended to decrease; the mean body length had decreased by 25 % since 2000. Abiotic variables related to seasonal variability (water level) and those affected by reservoir operation (water transparency and nutrients) explained the decrease in body size. Our results highlighted that larger Migratory Fish were found in the undammed river in lower transparency habitats.
-
interspecific variation in Migratory Fish recruitment in the upper parana river effects of the duration and timing of floods
Environmental Biology of Fishes, 2015Co-Authors: Anielly Galego De Oliveira, Harumi Irene Suzuki, L C Gomes, Angelo Antonio AgostinhoAbstract:This study evaluated the relationship between the young of year (YOY) abundance of Migratory Fish species and the interannual variations in the duration and delay of floods in the Upper Parana River floodplain. YOY of the most abundant Migratory species Brycon orbignyanus, Hemisorubim platyrhynchos, Leporinus elongatus, Leporinus macrocephalus, Leporinus obtusidens, Pseudoplatystoma corruscans, Pterodoras granulosus, Prochilodus lineatus, Salminus brasiliensis and Sorubim lima were studied in a stretch of the Parana river influenced by dams. Multiple regression analyses were performed with flood duration and delay as predictors for YOY abundances. There were differences among the species in the responses to flood duration and delay. The species B. orbignyanus, L. elongatus, L. macrocephalus, L. obtusidens, and P. lineatus exhibited an exponential increase in YOY abundance with flood duration. An exponential decrease in YOY abundance with flood delay was found for most of the studied species. Nevertheless, flood delay and flood duration were significant predictors of YOY abundance for L. elongatus, L. obtusidens, P. corruscans and P. lineatus. For these species, flood delays may result in failure of recruitment because these species migrate early in the season to adjust their energy reserves and their swimming patterns. Therefore, any efforts to preserve Migratory Fish should consider discharge manipulation from reservoirs upstream of the study areas. It is crucial that reservoirs are operated in such a way that the quantity, duration and timing of water release are compatible with the viability of spawning and the survival of early life stages of Migratory Fish.
-
Large reservoirs as ecological barriers to downstream movements of Neotropical Migratory Fish
Fish and Fisheries, 2014Co-Authors: Fernando Mayer Pelicice, Paulo Santos Pompeu, Angelo Antonio AgostinhoAbstract:Most large rivers in South America are fragmented by large dams, and a common management strategy to mitigate impacts has been construction of Fish passes. Recent studies, however, indicate that downstream passage of adults and young Fish is nil or minimal. Better understanding of this phenomenon is needed if Fishways are to provide any tangible conservation value in South America. We propose, in this article, that large reservoirs impose a different kind of barrier to migrating Fish: impoundments create a diffuse gradient of hydraulic/limnological conditions that affects Fish behaviour and functions as an extensive environmental filter that discourages downstream movements. To develop this idea, we characterize the barriers created by dams and reservoirs by describing their distinct nature, the effects on Fish migration and potential solutions. We show, for example, that dams generally prevent upstream movements, whereas reservoirs impede mainly downstream movements. In this context, we explain how Fish passes, in some instances, can partially mitigate fragmentation caused by dams, but there is no technical solution to solve the barrier effect of reservoirs. In addition, we present a body of empirical evidence that supports the theory that large reservoirs are important barriers to Fish migration in South America, we offer an overview of the size of reservoirs to show that impoundments typically have large dimensions, and we discuss the significance of this theory for other regions. Based on current and proposed river regulation scenarios, we conclude that conservation of Neotropical Migratory Fish will be much more complicated than previously believed.
Sergio Makrakis - One of the best experts on this subject based on the ideXlab platform.
-
importance of reservoir tributaries to spawning of Migratory Fish in the upper parana river
River Research and Applications, 2015Co-Authors: P S Da Silva, Sergio Makrakis, Leandro E. Miranda, Maristela Cavicchioli Makrakis, Lucileine De Assumpcao, S Paula, Joao Henrique Pinheiro Dias, Hugo MarquesAbstract:Regulation of rivers by dams transforms previously lotic reaches above the dam into lentic ones and limits or prevents longitudinal connectivity, which impairs access to suitable habitats for the reproduction of many Migratory Fish species. Frequently, unregulated tributaries can provide important habitat heterogeneity to a regulated river and may mitigate the influence of impoundments on the mainstem river. We evaluated the importance of tributaries to spawning of Migratory Fish species over three spawning seasons, by comparing several abiotic conditions and larval Fish distributions in four rivers that are tributaries to an impounded reach of the Upper Parana River, Brazil. Our study confirmed reproduction of at least 8 long-distance migrators, likely nine, out of a total of 19 occurring in the Upper Parana River. Total larval densities and percentage species composition differed among tributaries, but the differences were not consistent among spawning seasons and unexpectedly were not strongly related to annual differences in temperature and hydrology. We hypothesize that under present conditions, densities of larvae of Migratory species may be better related to efficiency of Fish passage facilities than to temperature and hydrology. Our study indicates that adult Fish are finding suitable habitat for spawning in tributaries, Fish eggs are developing into larvae, and larvae are finding suitable rearing space in lagoons adjacent to the tributaries. Our findings also suggest the need for establishment of protected areas in unregulated and lightly regulated tributaries to preserve essential spawning and nursery habitats. Copyright © 2014 John Wiley & Sons, Ltd.
-
ASCENT OF NEOTROPICAL Migratory Fish IN THE ITAIPU RESERVOIR Fish PASS
River Research and Applications, 2011Co-Authors: Sergio Makrakis, Leandro E. Miranda, Luiz Carlos Gomes, Maristela Cavicchioli Makrakis, H. M. F. JuniorAbstract:The Piracema Canal is a complex 10-km Fish pass system that climbs 120 m to connect the Parana River to the Itaipu Reservoir along the Brazil–Paraguay border. The canal was constructed to allow Migratory Fishes to reach suitable habitats for reproduction and feeding in tributaries upstream from the reservoir. The Piracema Canal attracted 17 of the 19 long-distance Migratory species that have been recorded in the Parana River Basin and Paraguay–Parana Basin. However, the incidence of Migratory Fish decreased from downstream to upstream, with the pattern of decrease depending on species. Overall, 0.5% of the Migratory Fish that entered the Piracema Canal and segment 1, eventually were able to reach segment 5 and potentially Itaipu Reservoir. Ascension rate was examined relative to various physical attributes of canal segments; maximum water velocity emerged as the most influential variable affecting Fish passage. Water velocity may be manipulated by controlling water discharge, and by re-engineering critical sections of the canal. Because the Itaipu Reservoir flooded a set of falls that separated two distinct biogeographical regions, facilitating Fish movements through the Piracema Canal into the Itaipu Reservoir presents a management dilemma that requires deliberation in the context of the Fish assemblages rather than on selected Migratory species. Copyright © 2010 John Wiley & Sons, Ltd.
Alex Haro - One of the best experts on this subject based on the ideXlab platform.
-
swimming performance of upstream migrant Fishes in open channel flow a new approach to predicting passage through velocity barriers
Canadian Journal of Fisheries and Aquatic Sciences, 2004Co-Authors: Alex Haro, Theodore Castrosantos, John Noreika, Mufeed OdehAbstract:The ability to traverse barriers of high-velocity flow limits the distributions of many diadromous and other Migratory Fish species, yet very few data exist that quantify this ability. We provide a...
-
swimming performance of upstream migrant Fishes in open channel flow a new approach to predicting passage through velocity barriers
Canadian Journal of Fisheries and Aquatic Sciences, 2004Co-Authors: Alex Haro, Theodore Castrosantos, John Noreika, Mufeed OdehAbstract:The ability to traverse barriers of high-velocity flow limits the distributions of many diadromous and other Migratory Fish species, yet very few data exist that quantify this ability. We provide a detailed analysis of sprint swimming ability of six Migratory Fish species (American shad (Alosa sapidissima), alewife (Alosa pseudoharengus), blueback herring (Alosa aestivalis), striped bass (Morone saxatilis), walleye (Stizostedion vitreum), and white sucker (Catostomus commersoni)) against controlled water velocities of 1.54.5 m·s1 in a large, open-channel flume. Performance was strictly voluntary: no coercive incentives were used to motivate Fish to sprint. We used these data to generate models of maximum distance traversed, taking into account effects of flow velocity, body length, and temperature. Although the maximum distance traversed decreased with increasing velocity, the magnitude of this effect varied among species. Other covariate effects were likewise variable, with divergent effects of tempera...