scholarly journals Passage Performance of Potamodromous Cyprinids over an Experimental Low-Head Ramped Weir: The Effect of Ramp Length and Slope

2019 ◽  
Vol 11 (5) ◽  
pp. 1456 ◽  
Author(s):  
Susana Amaral ◽  
Paulo Branco ◽  
Christos Katopodis ◽  
Maria Ferreira ◽  
António Pinheiro ◽  
...  
Keyword(s):  
Cost Effective ◽  
Fish Passage ◽  
Habitat Connectivity ◽  
Intermediate Level ◽  
Fish Movements ◽  
Future Studies ◽  
Relative Contribution ◽  
Low Head ◽  
Passage Efficiency

Low-head ramped weirs are a common instream obstacle to fish movements. Fish passability of these structures, where water passes over but does not generate a waterfall, is primarily related to ramp length and slope, but their relative contribution has seldom been considered. This study aims to assess the passage performance of a potamodromous cyprinid, the Iberian barbel (Luciobarbus bocagei), negotiating an experimental ramped weir with varying ramp length (L) and slope (S). Four configurations were tested, with a constant discharge of 110 L∙s−1. Results suggest that both factors influenced passage performance of fish. Attraction efficiency (AE) increased with increasing L and S, whereas the number of successes (N) and passage efficiency (PE) decreased upon increasing L. For S, it was found that both N and PE peaked at the intermediate level (20%). These results suggest that configurations with the lowest slopes may not necessarily be the best option because they may be less attractive for the fish and their demand for space is higher. Higher slopes (but not excessive) could be more attractive to fish, less space-demanding, and therefore, more cost-effective. Future studies should investigate how discharge and boulder placement influence fish passage across ramped weirs, to improve habitat connectivity.

scholarly journals Evaluation of Low-Head Ramped Weirs for a Potamodromous Cyprinid: Effects of Substrate Addition and Discharge on Fish Passage Performance, Stress and Fatigue

Water ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 765
Author(s):  
Susana D. Amaral ◽  
Paulo Branco ◽  
Filipe Romão ◽  
Maria Teresa Ferreira ◽  
António N. Pinheiro ◽  
...  
Keyword(s):  
Physiological Responses ◽  
Fish Passage ◽  
Physiological Parameters ◽  
Blood Samples ◽  
Fish Movements ◽  
Unit Width ◽  
Q 55 ◽  
Specific Discharge ◽  
Low Head ◽  
Substrate Addition

Requalification of low-head ramped weirs through the addition of substrates (retrofitting) has attracted attention in recent years. However, few studies are available on how this measure affects the negotiation of ramped weirs by fish. This study aimed to assess the performance of an experimental ramped weir (3.00 m long with 10% slope; 0.30 m head-drop) to enhance the passage of a potamodromous cyprinid species, the Iberian barbel (Luciobarbus bocagei). Attention was given to testing the effects of the addition of a substrate, in this case cobbles, to the ramp (Nature) vs. a smooth bottom (Control), and discharge (Q; 55 L·s−1 and 110 L·s−1 (or specific discharge per unit width, q = 92 L·s−1·m−1 and 183 L·s−1·m−1)) on fish passage performance. Fish physiological responses to stress and fatigue, measured by glucose and lactate concentrations in blood samples, were also analysed. Results showed that the Nature design generally increased fish movements and successful upstream passages, and enhanced fish passage performance by enabling faster negotiations. Fish movements were also affected by increasing discharge, registering reductions with 110 L·s−1. Results of the physiological parameters indicate that both glucose and lactate concentrations were also influenced by discharge. The outcomes from this study present important information about fish passage performance across low-head ramped weirs and could provide data needed to help biologists and engineers to develop more effective structures to alleviate small instream obstacles.

scholarly journals Assessment of Retrofitted Ramped Weirs to Improve Passage of Potamodromous Fish

Water ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 2441 ◽  
Author(s):  
Susana D. Amaral ◽  
Ana L. Quaresma ◽  
Paulo Branco ◽  
Filipe Romão ◽  
Christos Katopodis ◽  
...  
Keyword(s):  
Decision Making ◽  
Numerical Modelling ◽  
Spatial Arrangement ◽  
Fish Passage ◽  
Hydrodynamic Conditions ◽  
Natural Substrate ◽  
Fish Movements ◽  
Low Head ◽  
Support Decision Making ◽  
Water Depths

The addition of substrates to small instream obstacles, like low-head ramped weirs, has been considered a useful management solution to retrofit those structures and enhance fish passage. Substrate dimensions and spatial arrangement, together with discharge, and consequently water depths, appear as important factors for the creation of hydrodynamic conditions that may facilitate the successful passage of fish, though related studies are scarce to support decision-making. This study assessed the influence of discharge (Q) and different retrofitting designs (RD) on the upstream passage performance of a potamodromous cyprinid, the Iberian barbel (Luciobarbus bocagei). Different substrates (small boulders, large boulders, cobbles) and spatial arrangements (aligned, offset) were tested. Numerical modelling was performed to characterize the hydrodynamics. Results indicate that Q and RD influenced the upstream negotiation of ramped weirs. Cobbles randomly distributed along the ramp (Nature design) was the most successful configuration, recording the highest number of upstream passages. Low velocities along the ramp, and low turbulence downstream, were registered in this configuration, indicating that the use of natural substrate may help to increase the permeability of ramped weirs to fish movements. The outcomes from this work can help engineers and biologists to design more appropriate passage structures for low-head instream obstacles.

scholarly journals Preserving the Activities of Daily Living Independence in Late Life

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 228-228
Author(s):  
Pao-feng Tsai ◽  
Thomas Jakobs ◽  
Reid Landes
Keyword(s):  
Training Program ◽  
Daily Living ◽  
Cost Effective ◽  
Computer Application ◽  
Maximum Effect ◽  
Activity Of Daily Living ◽  
Nursing Assistant ◽  
Future Studies ◽  
Certified Nursing Assistant

Abstract Levels of Assistance (LoA) is an effective caregiving intervention for maintaining activity of daily living (ADL) independence. It is a structured, almost prescriptive, approach to encourage completing ADLs as independently as an elder’s capabilities permit. With appropriate prompts and assistance during dressing, elders can overcome disability, express retained competencies, and experience success. Simultaneously, caregivers learn to view their functions as maintaining the quality of life of able elders, and they receive reinforcement from elders who are more confident and happier. This study is a continuation of a previous project that created and tested a computer application training program for LoA in nursing homes. We refined the app to include grooming LoA and tested on 10 certified nursing assistant (CNA)/resident dyads at a local nursing home. The pilot results showed, although we did not see consistent improvement in CNA’s dressing LoA, we achieved 10% to 30% improvement in grooming LoA. This indicates that the dressing assistance training is able to transfer to grooming LoA. With only an average of one-hour app training, this improvement is cost effective as compared to training provided by care professionals. Future studies should consider incorporating a culture change strategy to improve CNAs’ intention for assisting elders. In addition, the training program should be offered in the initial hire to achieve maximum effect.

scholarly journals Genome-wide markers reveal differentiation between and within the cryptic sister species, sunset and vermilion rockfish

2021 ◽  
Author(s):  
Gary C. Longo ◽  
John Harms ◽  
John R. Hyde ◽  
Matthew T. Craig ◽  
Ana Ramón-Laca ◽  
...  
Keyword(s):  
Management Strategies ◽  
Cost Effective ◽  
Sister Species ◽  
Nucleotide Polymorphisms ◽  
Relative Contribution ◽  
Genetic Groups ◽  
Cost Effective Method ◽  
Species Population ◽  
Single Complex ◽  
Species Specific

AbstractThe vermilion rockfish complex, which consists of the cryptic sister species vermilion and sunset rockfish, is one of the most valuable recreational fisheries on the U.S. West Coast. These species are currently managed as a single complex, and because of uncertainty surrounding the relative contribution of each species within existing data sources, the stock status of each species is not fully known. A reliable and cost-effective method is needed to disentangle these species that will allow for the development of abundance indices, life history profiles, and catch histories that may potentially support species-specific stock assessments. Using restriction-site associated DNA sequence (RADseq) markers we generated 10,003 polymorphic loci to characterize the vermilion rockfish complex. PCA and Bayesian clustering approaches based on these loci clearly distinguished between sunset and vermilion rockfishes and identified hybrid individuals. These loci included 203 highly differentiated (FST ≥ 0.99) single nucleotide polymorphisms, which we consider candidates in the planned development of a diagnostic assay capable of distinguishing between these cryptic species. In addition to clearly delineating to species, subsets of the interspecific markers allowed for insight into intraspecific differentiation in both species. Population genetic analyses for sunset rockfish identified two weakly divergent genetic groups with similar levels of genetic diversity. Vermilion rockfish, however, were characterized by three distinct genetic groups with much stronger signals of differentiation and significantly different genetic diversities. Collectively, these data will contribute to well-informed, species-specific management strategies to protect this valuable species complex.

scholarly journals Do beaver dams reduce habitat connectivity and salmon productivity in expansive river floodplains?

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2403 ◽  
Author(s):  
Rachel L. Malison ◽  
Kirill V. Kuzishchin ◽  
Jack A. Stanford
Keyword(s):  
Fish Assemblages ◽  
Coho Salmon ◽  
Fish Passage ◽  
Main Channel ◽  
Habitat Connectivity ◽  
Juvenile Salmon ◽  
Negative Consequences ◽  
Alluvial Rivers ◽  
Beaver Ponds ◽  
Beaver Dams

Beaver have expanded in their native habitats throughout the northern hemisphere in recent decades following reductions in trapping and reintroduction efforts. Beaver have the potential to strongly influence salmon populations in the side channels of large alluvial rivers by building dams that create pond complexes. Pond habitat may improve salmon productivity or the presence of dams may reduce productivity if dams limit habitat connectivity and inhibit fish passage. Our intent in this paper is to contrast the habitat use and production of juvenile salmon on expansive floodplains of two geomorphically similar salmon rivers: the Kol River in Kamchatka, Russia (no beavers) and the Kwethluk River in Alaska (abundant beavers), and thereby provide a case study on how beavers may influence salmonids in large floodplain rivers. We examined important rearing habitats in each floodplain, including springbrooks, beaver ponds, beaver-influenced springbrooks, and shallow shorelines of the river channel. Juvenile coho salmon dominated fish assemblages in all habitats in both rivers but other species were present. Salmon density was similar in all habitat types in the Kol, but in the Kwethluk coho and Chinook densities were 3–12× lower in mid- and late-successional beaver ponds than in springbrook and main channel habitats. In the Kol, coho condition (length: weight ratios) was similar among habitats, but Chinook condition was highest in orthofluvial springbrooks. In the Kwethluk, Chinook condition was similar among habitats, but coho condition was lowest in main channel versus other habitats (0.89 vs. 0.99–1.10). Densities of juvenile salmon were extremely low in beaver ponds located behind numerous dams in the orthofluvial zone of the Kwethluk River floodplain, whereas juvenile salmon were abundant in habitats throughout the entire floodplain in the Kol River. If beavers were not present on the Kwethluk, floodplain habitats would be fully interconnected and theoretically could produce 2× the biomass (between June–August, 1,174 vs. 667 kg) and rear 3× the number of salmon (370,000 vs. 140,000) compared to the existing condition with dams present. The highly productive Kol river produces an order of magnitude more salmon biomass and rears 40× the individuals compared to the Kwethluk. If beavers were introduced to the Kol River, we estimate that off-channel habitats would produce half as much biomass (2,705 vs. 5,404 kg) and 3× fewer individuals (1,482,346 vs. 4,856,956) owing to conversion of inter-connected, productive springbrooks into inaccessible pond complexes. We concluded that beaver dams may limit the total amount of floodplain habitat available for salmon rearing in the Kwethluk river and that the introduction of beavers to the Kol river could be detrimental to salmon populations. The introduction of beavers to other large alluvial rivers like those found in Kamchatka could have negative consequences for salmon production.

scholarly journals Upstream passage of adult sea trout (Salmo trutta) at a low-head weir with an Archimedean screw hydropower turbine and co-located fish pass

2018 ◽  
Vol 69 (12) ◽  
pp. 1822 ◽  
Author(s):  
Jamie R. Dodd ◽  
Jonathan D. Bolland ◽  
Jon Hateley ◽  
Ian G. Cowx ◽  
Sam E. Walton ◽  
...  
Keyword(s):  
Salmo Trutta ◽  
Best Practice ◽  
Fish Passage ◽  
Green Energy ◽  
Small Scale ◽  
Sea Trout ◽  
Fish Pass ◽  
Wide Range ◽  
Negative Effect ◽  
Low Head

The exploitation of riverine systems for renewable energy has resulted in large numbers of small-scale hydropower schemes on low-head weirs. Although considered a clean and ‘green’ energy source in terms of emissions, hydropower can affect upstream migrating species by diverting flow away from viable routes over the impoundment and attract fish towards the turbine outfall. In an attempt to reduce this negative effect, hydropower outfalls with co-located fish-passage entrances are recommended, utilising turbine flows to attract fish towards the fish pass. The present study used acoustic telemetry to understand the performance of a co-located Larinier fish pass at a low-head hydropower scheme at a weir on the tidal Yorkshire Esk, England. The majority of the sea trout (anadromous Salmo trutta L.) individuals that approached the impediment were attracted to the hydropower and the co-located fish pass. Fish ascended through the pass under a wide range of river flows, tide heights, downstream river levels and hydropower flows, and there was no evidence that the hydropower operation affected fish-pass ascent. The information presented is urgently required to inform management decisions on the operation of hydropower schemes during the migratory period of salmonid fish, and help determine best-practice designs and operation at these facilities.

Flow structure and fish passage performance of a brush-type fish way: a field study in the İyidere River, Turkey

2019 ◽  
Vol 70 (11) ◽  
pp. 1619 ◽  
Author(s):  
Serhat Kucukali ◽  
Bülent Verep ◽  
Ahmet Alp ◽  
Davut Turan ◽  
Tanju Mutlu ◽  
...  
Keyword(s):  
Flow Structure ◽  
Fish Species ◽  
Total Body Length ◽  
Fish Passage ◽  
Hydropower Plant ◽  
Small Hydropower ◽  
Black Sea Region ◽  
Fish Pass ◽  
Target Fish ◽  
Passage Efficiency

The fish passage performance and flow structure of a brush fish pass were investigated at the İncirli Small Hydropower Plant on the İyidere River, located in the East Black Sea region of Turkey. The spatial distributions of velocity vectors, power velocity, Froude number and turbulent kinetic energy are presented. The flow is quasi-uniform and subcritical, which provides different migration corridors with favourable hydraulic conditions; importantly for the fish, these corridors continue through the complete fish pass. The flow–bristle interaction creates a reduced velocity and low-turbulence resting zones. In addition, the passage efficiency of the brush fish pass was assessed using passive integrated transponder telemetry. The results clearly showed that upstream passage efficiency differs between fish species: Salmo coruhensis performed better than Alburnoides fasciatus on the same fish passage. The passage efficiency for the target fish species S. coruhensis was calculated to be 82.4%. The data revealed that the brush fish passage provides passage for small-bodied fish (total body length <15cm) in a high-gradient channel with a slope of 10%. The monitoring data revealed that bristles as flexible hydraulic elements are beneficial for migrating fish.

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