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Salmo salar; Salmo trutta; anadromous fish; body size; freshwater; life history; population size; salmon; sport fishing; time series analysis; trout; watersheds; Scotland; Southern European region
Abstract:
... We use a long time series of catch abundance from a recreational fishery over 116 years to look for population trends in Atlantic salmon, and anadromous (sea trout) and non-anadromous (brown) trout for a single catchment, Loch Lomond, west central Scotland. Year strongly predicted variation in catches but catch effort did not meaningfully increase explained variation. Salmon showed periods of incr ...
... Habitat degradation combined with climate change increases the threat of extinction for stream fishes. In response to these threats, efforts to reestablish species within formerly occupied streams or translocation to suitable areas may be effective conservation strategies. In the absence of historic species presence data, identifying locations where suitable habitat exists across many fluvial habi ...
Nils Teichert; Anne Lizé; Hélène Tabouret; Claudia Gérard; Gilles Bareille; Anthony Acou; Alexandre Carpentier; Thomas Trancart; Laure-Sarah Virag; Emma Robin; Morgan Druet; Jordan Prod’Homme; Eric Feunteun
body condition; eel; estuaries; freshwater; life history; lipids; otoliths; parasites; rivers; silver; trophic levels; water power; watersheds
Abstract:
... River fragmentation is expected to impact not only movement patterns and distribution of eels within catchment, but also their life-history traits. Here, we used otolith multi-elemental signatures to reconstruct life sequences of European silver eels within an obstructed catchment, just before the removal of hydropower dams. Beyond providing an initial state, we hypothesized that otolith signature ...
fish; habitats; hydrograph; hydrologic data; power generation; river flow; time series analysis; Canada
Abstract:
... Setting e-flows (instream, environmental or ecological flow regimes) for existing or new hydroelectric and other projects is a key worldwide consideration. A Canadian perspective and experience in arriving at e-flow regimes for ice-free or ice-covered rivers, with emphasis on small and large hydroelectric projects, is presented through general concepts and modeling approaches. Rather than a single ...
... The mathematical prediction of the growth of submerged macrophytes provides direct inference in harvest management, estimation of habitat structuring, and calculation of incidence areas, in function to the main environmental constraints. The aim of this study was to enable us the equivalence between the liquid photosynthetic rates (obtained from the light and dark flasks method) and the growth rat ...
... Invertebrate drift is a key process in riverine ecosystems controlling aquatic invertebrate distribution and availability to fish as prey. However, accurately quantifying drifting invertebrates of all sizes is difficult because the fine-mesh nets required to capture the smallest specimens clog easily, which reduces filtration efficiency and measurement accuracy. To address this problem, we develop ...
energy; sustainable development; water power; Brazil; Canada; Norway
Abstract:
... Sustainable global energy production is back-stopped by hydropower which is responsible for a significant share of the green energy produced worldwide. Hydropower, however, does not come without some environmental impacts but has worked to reduce those impacts. Here, we discuss the historical, legislative, and design configurations of hydropower facilities located in three of the world’s most impo ...
... We explore how anomalously strong winter storms, superposed with managed nitrogen reduction, impacted the 2010 and 2018 spring blooms in the Narragansett Bay (41.62° N, 71.35° W). Anomalously strong winter storms preceding spring of 2010 and 2018 increased annual nutrient inputs above the long-term average annual values for the year, causing a large phytoplankton bloom in spring 2010 and a massive ...
Salmo salar; dissolved gases; gas bubble disease; mortality; risk; smolts; water power; Norway
Abstract:
... Total dissolved gas (TDG) supersaturation downstream of hydropower plants may cause gas bubble disease (GBD) and harmful effects in fish. Little is known about tolerance levels of TDG supersaturation on Atlantic salmon (Salmo salar Linnaeus, 1758) in natural rivers. The present study investigated the effects of TDG supersaturation on the survival of Atlantic salmon smolts at two field sites in Nor ...
... The resting eggs of large branchiopods do not hatch all at once during a hydroperiod; instead, a fraction of the eggs are left dormant to cope with unstable conditions in temporary wetlands. In order to maximize fitness, the fraction that terminates diapause is modified by signals indicating habitat suitability and biotic interactions. Here, in a laboratory experiment, we investigate the effect of ...
... The blue and red shrimp Aristeus antennatus has been intensively exploited by trawling fishery in the Western Mediterranean Sea. Implementation of an adequate management plan needs complete genetic data of the non-spawning and spawning grounds of the species. During the reproductive period, the species forms spawning aggregations in the middle slope, mainly constituted of mature females carrying s ...
Esox lucius; Salmo trutta; anadromous fish; genetic variance; genetic variation; phenotype; population genetics; predation; probability; rivers; smolts; water power
Abstract:
... By hindering migration and inducing direct turbine mortality during downstream migration, hydropower is regarded as one of the most serious threats to anadromous salmonids. Yet, little attention has been paid to long-term turbine-induced selection mechanisms effecting fish populations. This work evaluates turbine and post-turbine survival of PIT-tagged wild brown trout smolts. By estimating indivi ...
... Many freshwater mussel species are critically imperiled, and propagation is essential for species ‘recovery.’ Fungal contamination can negatively affect in vitro propagation of freshwater mussels; thus, we investigated methods of mitigating fungal contamination. Specifically, we tested the effect of medium replacement frequency and antifungal (Amphotericin B) concentrations on risk of fungal conta ...
... Valle Mandriole is one of the two last remaining freshwater wetlands in the coastal area of Ravenna (NE Italy). In 2011, a management technique that involves the complete drainage of the southern portion of Valle Mandriole during summer has been undertaken. In the present study, the effects of this artificial drying on the benthic macroinvertebrate fauna were assessed using a beyond before-after-c ...
adaptive management; fish; politics; power generation; rivers; water power; British Columbia
Abstract:
... Most of the hydropower generated in Canada’s western province of British Columbia is generated by a small number of large storage or diversion projects that impound large rivers. All but one were built between 1950 and 1985; a period when environmental considerations for large projects were evolving to present-day social, political and regulatory standards. Large projects result in ecosystem trans ...
... Phytoplankton biomass data often involve zero outcomes preventing a description by continuous distributions with positive support such as the lognormal distribution commonly used to describe ecological data. Two usual solutions: ignoring the zeroes and adding a small positive number to all outcomes, induce bias and reduce predictive power. To address these shortcomings, we design a Bayesian two-pa ...
... The monkey goby Neogobius fluviatilis is an invasive Ponto-Caspian fish that enters habitats of the native gudgeon Gobio gobio in European freshwaters, likely belonging to the same prey guild. Their abilities to detect and avoid predation have been poorly understood, although these traits may contribute to the competitive advantage and drive the invasion success of the goby. We tested intra- and i ...
... Considering the pivotal role played by erosive organisms in the marine habitat and the scanty knowledge of this phenomenon in the Mediterranean Sea, the present study aimed to identify the pioneer excavating organisms occurring in the first stages of bioerosion, providing the first estimation of their rate of erosion along the North Adriatic Sea. Bioerosion activity was investigated by deploying s ...
body size; dominant species; fish; species abundance; streams; Brazil
Abstract:
... Even after more than a century of research, the processes underlying species abundance distribution patterns are controversial. Here, we gathered abundance and size (standard length) data of fish species in 54 streams in the Midwest of Brazil to test whether subordinate species abundances (i.e., any species that is not dominant in a community) in each stream are correlated with the absolute size d ...
... Theory predicts that species can only coexist if they are sufficiently different in their resource and/or microhabitat utilization; if their needs are too similar, the stronger population will exclude the weaker, unless the two species are equally strong competitors. This hypothesis is difficult to assess in most species because populations are limited by multiple resources simultaneously. In herm ...
... The diet and distribution of native (Hypostomus ancistroides, Hypostomus sp.) and exotic juvenile Loricariidae fish (Hypostomus cochliodon, Loricariichthys platymetopon, Pterygoplichthys ambrosettii) from a Neotropical floodplain were analyzed, aiming to understand if these factors contribute to coexistence. Sampling was conducted from 2002 to 2015 in two biotopes (river and lake) of the Ivinheima ...
... While many studies provide microscale relationships between fish and habitat characteristics, studies covering longer river reaches are scarce. Modern remote sensing techniques may enable new and effective ways of mapping and assessing mesoscale habitat characteristics. Using green LIDAR-derived bathymetry and hydraulic modelling, we tested how mesoscale depth and velocity were related to fish cou ...
... Salinity changes in transitional water ecosystems are a natural feature, but anthropogenic direct or indirect impacts are drastically altering their equilibrium and, therefore, their biological communities. Females of three species of Palaemonidae shrimps (the invasive Palaemon macrodactylus and the native P. adspersus and P. elegans) were collected in nature and kept in laboratory at salinities 2 ...
... Invasive species cause substantial changes to the biodiversity of freshwater systems. The African Nile tilapia (Oreochromis niloticus) is now widely distributed in tropical freshwaters globally. Despite indications that feral populations can influence native species through competitive effects, direct evidence of competition between Nile tilapia and native species is rare. Moreover, it is not clea ...
Renato T. Martins; Janaina Brito; Karina Dias-Silva; Cecília G. Leal; Rafael P. Leitão; Vivian C. Oliveira; José M. B. Oliveira-Júnior; Felipe R. de Paula; Fabio O. Roque; Neusa Hamada; Leandro Juen; Jorge L. Nessimian; Paulo S. Pompeu; Robert M. Hughes
... Stream degradation in Amazonia is outpacing our ability to effectively monitor it for three key reasons: (1) Many changes are cumulative and occur gradually; (2) Scientists have failed to clearly link anthropogenic disturbances with ecological and economic indicators of concern to decision makers and the public; (3) There are too many potential indicators to assess in a cost-effective manner. Ther ...
... In this paper, we investigated composition and trait turnover among fish assemblages in reservoirs distributed across major Brazilian basins, in order to contrast taxonomic and functional turnover and to investigate their respective drivers. We investigated the hypothesis that reservoir assemblages present, on a continental scale, divergent species compositions but with a similar set of traits. Sp ...
Violeta Martínez-Castillo; Alma Paola Rodríguez-Troncoso; José de Jesús Adolfo Tortolero-Langarica; Eric Bautista-Guerrero; Jacqueline Padilla-Gamiño; Amílcar Leví Cupul-Magaña
Pavona; bioerosion; calcification; corals; nitrates; nitrites; phosphates; urban development
Abstract:
... Reef development occurs commonly under oligotrophic conditions that favor corals over competitors. In the Eastern Tropical Pacific (ETP), coral communities develop under highly dynamic environmental conditions that may benefit organisms involved in reef bioerosion. To understand how coral performance and maintenance change with increasing urban pressure in the ETP, we evaluated coral reproductive ...
Cobitis; basins; diploidy; museums; polyploidy; rivers; space and time; Eastern European region
Abstract:
... An expansion of a species range may happen unnoticed when an expanding species is similar in appearance to local species and distinguishable mainly by genetic methods. The morphological similarity of polyploid spined loaches of the hybrid complex Cobitis elongatoides–taenia–tanaitica with their diploid relatives makes their recent expansion in the rivers of Eastern Europe truly cryptic. We confirm ...
Dolichospermum; Microcystis; Raphidiopsis; World Health Organization; autumn; biomass; lakes; spring; subtropics; total nitrogen; total phosphorus; water quality; water supply; Queensland; South Australia
Abstract:
... The objective of this study was to identify correlations between environmental variables and cyanobacterial diversity, succession and dominance in three Australian water supply reservoirs. We assessed up to 15 years of in-lake water quality monitoring data from Lake Wivenhoe and Lake Tingalpa (Queensland), and Lake Myponga (South Australia). Lakes Wivenhoe and Tingalpa, subject to a subtropical cl ...
... We present an extensive DNA barcoding study of the fish species of the Lake Edward system, including information on intraspecific variation. The DNA barcode gene, cytochrome c oxidase I (COI), failed to discriminate the 35 species of the genus Haplochromis analysed. For the non-Haplochromis species, the reference library had a near complete coverage of 91.2%, with 31 out of the 34 known species of ...
DNA barcoding; Tardigrada; fauna; freshwater; habitats; risk
Abstract:
... Rock pools are ephemeral freshwater habitats characterized by their small size, well-defined boundaries, and periodic desiccation, making them ideal model systems to answer numerous ecological questions. Although there are numerous studies on rock pool fauna around the world, tardigrades have only rarely been recorded. We conducted the first tardigrade-focused study on rock pools by quantitatively ...
... Native communities can resist the establishment and invasion of alien species through consumptive and/or competitive interactions. The extent of consumptive resistance from freshwater fish to the invasion of zebra mussels Dreissena polymorpha, a globally invasive Ponto-Caspian species, was assessed in two areas in Britain using stable isotope analysis, where mixing models predicted the contributio ...
Bacillariophyceae; data collection; plankton; rivers; seasonal variation; species diversity; summer
Abstract:
... Comparing spatio-temporal patterns between planktonic and benthic algae is helpful for understanding their associations and differences. However, such studies are still rare especially in large rivers. We used a dataset collected in the upper reach of the Jinsha River in different seasons to explore biodiversity and assembly processes of planktonic and benthic diatom assemblages. We found that pla ...
climate; data collection; ecosystem management; freshwater; geographical distribution; lotic systems; macroinvertebrates; model validation; rivers; variance
Abstract:
... Lotic freshwater macroinvertebrate species distribution models (SDMs) have been shown to improve when hydrological variables are included. However, most studies to date only include data describing climate or stream flow-related surrogates. We assessed the relative influence of climatic and hydrological predictor variables on the modelled distribution of macroinvertebrates, expecting model perform ...
... Reductions in aquatic habitat size facilitate encounters between predators and prey by reducing the height of the water column and the water volume. Here, we proposed to disentangle the effects of these mechanisms on predation rates and parameters of functional response curves of predators. We paired active-search predators (Buenoa, Hemiptera) or ambush predators (Pantala and Lestes, Odonata) with ...
fish; fish ladders; larvae; lentic systems; lotic systems; rain; rivers; summer; water power; Brazil
Abstract:
... This study was conducted to investigate fish eggs and larvae dispersal in a river stretch influenced by small hydropower plants in Southeast Brazil. The main hypothesis is that the downstream dispersal of free-flowing eggs and larvae is likely to occur given the small size of the studied reservoirs and that passage through the dam may occur, with the fish ladder contributing to it. Eggs and larvae ...
Chironomidae; climate change; correspondence analysis; freshwater; groundwater; indicator species; integument; littoral zone; pupae; salinity; species diversity; water quality; water temperature; watersheds; Mongolia
Abstract:
... The Great Lakes region of western Mongolia includes a diversity of lake ecosystems, from alpine freshwater to lowland, saline lakes, which increasingly face environmental threats from excessive grazing and climate change. We assessed environment-species relationships and patterns of biodiversity of non-biting midges (Diptera: Chironomidae) in 55 western Mongolian lakes using surface-floating pupal ...
... Mining activities often produce large amounts of pollutants that lead to streams affecting aquatic biota. Aquatic insects have a key role in energy transference from streams to terrestrial systems since emergent insects contribute to the diet of riparian predators. If streams are polluted, emergent insects may act as pollutant conveyors from water to land. Our objective was to investigate if insec ...
Cyprinidae; Esox lucius; Micropterus salmoides; community structure; corn; fish communities; freshwater; littoral zone; pet foods; probability; species richness; Ontario
Abstract:
... Methods for the use of baited remote underwater video stations (BRUVS) have been tested and refined such that they are now widely used in marine research for assessing fish community structure. There is comparatively less known about the effectiveness of different bait types or bait containers for use with BRUVS in freshwater temperate environments. We conducted a field-based experiment in Lake Op ...
... Global decline of freshwater mussels (Unionoida) is threatening biodiversity and the essential ecosystem services that mussels provide. As filter-feeding organisms, freshwater mussels remove phytoplankton and suspended particles from the water. By filtering bacteria, freshwater mussels also decrease pathogen loads in the water. The objective of this study was to evaluate whether the common freshwa ...
Neotropics; hydrodynamics; migratory behavior; potamodromous fish; water power; Brazil
Abstract:
... This study identifies hydrodynamic alterations in flow downstream of a dam that are related to hydropower plant (HPP) operation and that might attract Neotropical potamodromous fish to unsafe places in the tailrace during their reproductive migration. Our hypotheses are (1) the hydrodynamic flow in the tailrace presents conditions that are strong attractive for fish than those found in the downstr ...
Acropora cervicornis; Miozoa; asexual reproduction; corals; early development; embryogenesis; lawns and turf; life history; sediments; Caribbean Sea; Colombia
Abstract:
... Acropora cervicornis underwent massive mortalities in the Caribbean Sea and its populations have failed to recover after several decades. This study aimed to document the early life history of A. cervicornis from embryogenesis to symbiotic dinoflagellates acquisition. Gametes were collected in Islas del Rosario (Colombia) and a cross-fertilization was performed ex situ. A settlement experiment was ...
... Cobias (Rachycentron canadum) are large fish that live in all the tropical oceans of the world, except for the Eastern Pacific Ocean (EPO). During 2015, a cobia cage culture was initiated in the EPO off Ecuador. Thousands of cobia individuals escaped from the culture, and the location of the escapees is unknown. In this paper, we used a Maximum Entropy (MaxEnt) model to assess the preferential hab ...
buried seeds; community structure; environmental factors; lentic systems; lotic systems; rivers; seedling emergence; species richness; stress tolerance; vegetation; France
Abstract:
... This research aimed to disentangle the role of the connectivity gradient as a dispersal and environmental filter. This was done by comparing community composition and plant strategies (i.e. competition, stress-tolerance and ruderalness) in the soil seedbank (SSB) to that in the standing vegetation (SV). The study took place in a disconnecting side channel of the Loire River (France). SV was record ...
Amphipoda; Oncorhynchus mykiss; antipredatory behavior; carbon; diet; food webs; littoral zone; omnivores; stable isotopes; trout; water birds; Argentina
Abstract:
... Rainbow trout have been stocked in naturally fishless lakes in the reproductive area of the endangered Hooded Grebe, an endemic aquatic bird of Southern Patagonia. The effects of trout introduction were proposed as one of the potential causes of their critical situation. Trout could modify the trophic structure of the aquatic community by altering the trophic relationships of stocked lakes. Change ...
... IUCN Red List assessments for fish species can quickly become out of date. In recent years molecular techniques have added new ways of obtaining information about species distribution or populations. In this work, we propose the Iberian Peninsula as an example of reassessment needs in its endangered freshwater fish fauna. We compiled the list of freshwater fish species occurring in continental Spa ...
Isopoda; Lepomis; Notemigonus crysoleucas; diet; fish; habituation; kairomones; photography; tap water
Abstract:
... The ability to detect predators at a distance through chemical cues is often essential for prey, but spatial variation in predator presence and species may promote variability in the reactions of prey subpopulations. We collected isopods (Caecidotea communis) from three ponds: two with fish (sunfish in one, shiners in the other), and one without. We exposed individuals from these three subpopulati ...
... Decomposition of allochthonous organic matter is an essential process in headwater streams. Damming of streams alters decomposition rates in the benthic zone downstream, but little is known about the effects on hyporheic decomposition. We examined the effects of dams on hyporheic and benthic organic matter decomposition, using the cotton-strip assay over five seasons, in two forest mountain stream ...
... Freshwater systems are projected to experience increased hydrologic extremes under climate change. To determine how small streams may be impacted by shifts in flow regimes, we experimentally simulated flow loss over the span of three summers in nine 50 m naturally fed stream channels. The aquatic insect community of these streams was sampled before, during, and after experimental drought treatment ...
... Wetlands are dynamic environments where aquatic organisms are affected by both predictable and unpredictable changes in hydrology. Understanding how abundant large-bodied predators respond to these changes is especially important in context of wetland restoration. We used satellite telemetry to investigate how individual (e.g., sex, size, body condition) and environmental factors influenced moveme ...