Factors affecting juvenile galaxiid fish passage at culverts

2011 ◽  
Vol 62 (1) ◽  
pp. 38 ◽  
Author(s):  
Katharina Doehring ◽  
Roger G. Young ◽  
Angus R. McIntosh
Keyword(s):  
Fork Length ◽  
Fish Passage ◽  
Water Velocity ◽  
Fish Movement ◽  
Migratory Fish ◽  
Factors Affecting ◽  
The World ◽  
Galaxias Maculatus ◽  
Habitat Variables

Alteration of urban streams by culverts is common throughout the world and is known to impede freshwater fish movement. The main objectives were therefore to investigate how different culvert characteristics (e.g. height, length, angle, perched v. non-perched) and habitat variables (e.g. water velocity, riverbed gradient) affect the passage success of juvenile inanga (Galaxias maculatus), a weak-swimming migratory fish. We determined whether passage of juvenile G. maculatus could be improved by installing a ramp at thirteen replicate in situ culverts in Nelson City, New Zealand. As expected, none of the 400 fish tested were able to pass undercut (i.e. perched) culverts before ramp installation (0% passage), compared with the 250 fish (65% passage) that were able to pass non-perched culverts. Significantly more fish (44% passage) reached perched culvert outlets when aided by the ramp. Passage success with the ramp depended on its length and angle, with fewer fish passing longer or steeper ramps. To provide upstream passage for weak-swimming species such as juvenile (fork length < 60 mm) G. maculatus, ramp length and angle should not exceed three metres and 20 degrees, respectively. With passage requirements known and mitigation processes in place, urban fish populations might be able to be sustained.

scholarly journals Utilising the boundary layer to help restore the connectivity of fish habitats and populations

2018 ◽  
Author(s):  
Jabin R. Watson ◽  
Harriet R. Goodrich ◽  
Rebecca L. Cramp ◽  
Matthew A. Gordos ◽  
Craig E. Franklin
Keyword(s):  
Habitat Fragmentation ◽  
Fish Species ◽  
Juvenile Fish ◽  
Fish Passage ◽  
Freshwater Ecosystems ◽  
Water Velocity ◽  
Fish Movement ◽  
Important Species ◽  
Significant Contributor ◽  
Remediation Design

SignificanceHabitat fragmentation is a significant contributor to the worldwide decline of freshwater ecosystem health, the most pervasive cause of which is culverts. Culverts act as a barrier to fish movement, impacting feeding, predator avoidance, spawning, and community structures. Here we show that a common remediation strategy that involves baffles, is detrimental to the successful passage of small bodied and juvenile fish at high velocities. To remedy this widespread problem, we present a novel remediation design that benefits a range of small-bodied species and juvenile fish at the same high velocities, regardless of morphology or ecological niche. The application of this remediation design may be expanded to any smooth surfaced anthropogenic structure, to improve fish passage and restore ecosystem functionality.AbstractCulverts are a major cause of habitat fragmentation in freshwater ecosystems, are a barrier to fish movement, and are regarded as a significant contributor in the decline of freshwater fish populations globally. To try to address this, various culvert remediation designs have been implemented, including the installation of vertical baffles and the provision of naturalistic (rock) substrates. While remediation strategies generally aim to reduce the velocity of water flowing through the structure, there is often resistance to their use because the resultant reduction in culvert discharge can negatively impact upstream flooding while also resulting in debris clogging and increased culvert maintenance costs. In addition, baffles markedly increase water turbulence that may be detrimental to passage by some fish species or size classes. Here we present some novel remediation designs that exploit the reduced water velocity in boundary layers along the culvert wall to enhance fish passage without significantly compromising discharge capacity. These longitudinal designs produce an expanded reduced velocity zone along the culvert margins that generate minimal turbulence. We show that these novel designs are significantly advantageous to the swimming endurance and traversability for six small-bodied Australian fish species. We also provide data on how and why some culvert baffle designs may impede small-bodied fish passage. This data scales with increasing water velocity, encompassing inter-specific differences in swimming capacity. These results have broad implications for fish community structure and the requirement of juvenile cohort of large-bodied commercially important species where baffles have been implemented to facilitate fish passage.

Factors affecting repatriation success of the endangered Italian agile frog (Rana latastei)

2008 ◽  
Vol 29 (2) ◽  
pp. 235-244 ◽  
Author(s):  
Mauro Fasola ◽  
Daniele Pellitteri-Rosa ◽  
Fabio Pupin ◽  
Stefano Scali ◽  
Roberto Sacchi ◽  
...  
Keyword(s):  
Human Disturbance ◽  
Habitat Management ◽  
Northern Italy ◽  
Habitat Characteristics ◽  
Field Surveys ◽  
Factors Affecting ◽  
Management Actions ◽  
The World ◽  
Habitat Variables ◽  
Rana Latastei

Abstract Repatriations and translocations are among the most frequent actions deployed for conservation of amphibians all over the world. However, very few studies have analysed the effectiveness of these actions. The aims of this study were i) to measure the success of repatriations of Rana latastei carried out within a conservation project in Lombardy (Northern Italy) from 1999 to 2001, and ii) to analyse how the environmental factors affected repatriation success. Eighteen ponds were surveyed from February to April 2006, for an overall of 45 field surveys. Each pond was carefully checked for frogs and egg masses. We classified each pond as newly excavated or pre-existing according to habitat management actions and we measured 16 variables concerning micro- and macro-habitat characteristics, human disturbance and presence of predators. Rana latastei was found in 33.3% of monitored sites and the repatriation outcome of tadpole release did not differ between newly excavated and non managed ponds. Habitat variables influenced the success of repatriations, which increased in sites with higher percentage of woodlands. Finally, repatriation outcome was also negatively influenced by human disturbance and predator occurrence.

Post-Hurricane Michael damage assessment using ADCIRC storm surge hindcast, image classification, and LiDAR

Shore & Beach ◽  
2019 ◽  
pp. 3-14 ◽  
Author(s):  
Joshua Davis ◽  
Diana Mitsova ◽  
Tynon Briggs ◽  
Tiffany Briggs
Keyword(s):  
Wave Energy ◽  
Field Studies ◽  
Feedback Mechanism ◽  
Water Velocity ◽  
Airborne Lidar ◽  
Storm Events ◽  
Magnetic Current ◽  
Coastal Mapping ◽  
Electro Magnetic

Wave forcing from hurricanes, nor’easters, and energetic storms can cause erosion of the berm and beach face resulting in increased vulnerability of dunes and coastal infrastructure. LIDAR or other surveying techniques have quantified post-event morphology, but there is a lack of in situ hydrodynamic and morphodynamic measurements during extreme storm events. Two field studies were conducted in March 2018 and April 2019 at Bethany Beach, Delaware, where in situ hydrodynamic and morphodynamic measurements were made during a nor’easter (Nor’easter Riley) and an energetic storm (Easter Eve Storm). An array of sensors to measure water velocity, water depth, water elevation and bed elevation were mounted to scaffold pipes and deployed in a single cross-shore transect. Water velocity was measured using an electro-magnetic current meter while water and bed elevations were measured using an acoustic distance meter along with an algorithm to differentiate between the water and bed during swash processes. GPS profiles of the beach face were measured during every day-time low tide throughout the storm events. Both accretion and erosion were measured at different cross-shore positions and at different times during the storm events. Morphodynamic change along the back-beach was found to be related to berm erosion, suggesting an important morphologic feedback mechanism. Accumulated wave energy and wave energy flux per unit area between Nor’easter Riley and a recent mid-Atlantic hurricane (Hurricane Dorian) were calculated and compared. Coastal Observations: JALBTCX/NCMP emergency-response airborne Lidar coastal mapping & quick response data products for 2016/2017/2018 hurricane impact assessments

A Cohesive Analysis of Factors Affecting the Tourist Destination Image of Delhi

2015 ◽  
Vol 1 (2) ◽  
Author(s):  
Usha Arora ◽  
Deepti Dabas Hazarika
Keyword(s):  
National Income ◽  
Destination Image ◽  
Pertinent Literature ◽  
Tourist Destination ◽  
Factors Affecting ◽  
Tourism Marketing ◽  
The World ◽  
National Capital ◽  
Destination Management Organizations ◽  
The City

Economies all over the world are moving towards a focus on services. Tourism has emerged as a major contributor to economies all over the world. This is why specific focus is being placed on tourism, as Destination Management Organizations (DMOs) concentrate their efforts on tourism. India has been one of the countries where the share of tourism in national income has steadily been increasing. As the national capital, the city of Delhi has a major role to play in the tourist inflow to the country, as well as within the country. Successful tourism marketing requires that the concepts of tourist destination and underlying factors are comprehended in detail. An analysis of the available, pertinent literature on the area shows the manner in which numerous factors come together to form the image of a tourist destination. In fact, it needs to be understood that image formation may be done differently for different consumers. This further necessitates a detailed study of the factors influencing tourist destination image.

scholarly journals Fish and Chaps: Some Ethnoarchaeological Thoughts on Fish Skin Use in European Prehistory

2020 ◽  
Vol 6 (1) ◽  
pp. 329-347
Author(s):  
Roman Vávra
Keyword(s):  
Cultural Norms ◽  
Museum Collections ◽  
Fish Skin ◽  
Subsistence Strategies ◽  
Factors Affecting ◽  
Archaeological Data ◽  
The World

AbstractThe following study summarizes the available ethnographical, historical, and archaeological data about the use of fish skin as a material. Fish skin and the methods of its processing are described. The fish skin utilisation accounts from around the world are collected in an organized matter. Afterwards the various factors affecting the use of this material are discussed and some concluding remarks about the further research possibilities are proposed. The use of fish skin does not appear to be based purely on climate, subsistence strategies, or the availability of fish, but also on cultural norms and traditions. Careful hypotheses can be made by using relational analogies, but ultimately a re-examination of museum collections or new archaeological discoveries are fundamental in furthering this field of research.

The Vyredox and Nitredox Methods of in situ Treatment of Groundwater

1988 ◽  
Vol 20 (3) ◽  
pp. 149-163 ◽  
Author(s):  
Carol Braester ◽  
Rudolf Martinell
Keyword(s):  
Water Treatment ◽  
Surface Water ◽  
Traditional Method ◽  
Treatment Method ◽  
Nitrate Treatment ◽  
The Past ◽  
The World ◽  
Nitrate And Nitrite ◽  
Iron And Manganese

Nearly one fifth of all water used in the world is obtained from groundwater. The protection of water has become a high priority goal. During the last decades pollution of water has become more and more severe. Today groundwater is more and more used in comparison with surface water. Recently we have seen accidents, which can pollute nearly all surface water very quickly. Generally the groundwater is easier to protect, as well as cheaper to purify, and above all it is of better quality than the surface water. During the past two decades, alternatives to the traditional method of treating the water in filters have been developed, that is in situ water treatment i.e. the VYREDOX and NITREDOX methods. The most common problem regarding groundwater is too high content of iron and manganese, which can be reduced with the VYREDOX method. In some areas today there are severe problems with pollution by hydrocarbons and nitrate as well, and with modification of the VYREDOX treatment method it is used for hydrocarbon and nitrate treatment as well. The method to reduce the nitrate and nitrite is known as the NITREDOX method.

scholarly journals Prioritizing native migratory fish passage restoration while limiting the spread of invasive species: A case study in the Upper Mississippi River

2021 ◽  
pp. 148317
Author(s):  
Arthur R. Cooper ◽  
Dana M. Infante ◽  
Jesse R. O'Hanley ◽  
Hao Yu ◽  
Thomas M. Neeson ◽  
...  
Keyword(s):  
Invasive Species ◽  
Mississippi River ◽  
Fish Passage ◽  
Migratory Fish ◽  
Upper Mississippi River

Fabrication of monodisperse polypyrrole/SBA-15 composite for the selective removal of Cr(Ⅵ) from aqueous solutions

2021 ◽  
Author(s):  
Liang Wang ◽  
Peng Gao ◽  
Mengxin Liu ◽  
Ziqing Huang ◽  
Shixia Lan ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Aqueous Solutions ◽  
Adsorption Process ◽  
In Situ Polymerization ◽  
Selective Removal ◽  
Factors Affecting

Monodisperse polypyrrole/SBA-15 composite (PPy/SBA-15) was fabricated by in-situ polymerization and used for Cr(Ⅵ) adsorption from aqueous solution. PPy/SBA-15 was characterized by numerous approaches. Factors affecting the Cr(Ⅵ) adsorption process included...

Analysis of TBM Tunnel Behavior in Jointed Rock Mass

2011 ◽  
Vol 90-93 ◽  
pp. 2033-2036 ◽  
Author(s):  
Jin Shan Sun ◽  
Hong Jun Guo ◽  
Wen Bo Lu ◽  
Qing Hui Jiang
Keyword(s):  
Rock Mass ◽  
Numerical Models ◽  
Jointed Rock ◽  
In Situ Stress ◽  
Jointed Rock Mass ◽  
Joint Orientation ◽  
Joint Spacing ◽  
Factors Affecting ◽  
Dip Angle

The factors affecting the TBM tunnel behavior in jointed rock mass is investigated. In the numerical models the concrete segment lining of TBM tunnel is concerned, which is simulated as a tube neglecting the segment joint. And the TBM tunnel construction process is simulate considering the excavation and installing of the segment linings. Some cases are analyzed with different joint orientation, joint spacing, joint strength and tunnel depth. The results show that the shape and areas of loosing zones of the tunnel are influenced by the parameters of joint sets and in-situ stress significantly, such as dip angle, spacing, strength, and the in-situ stress statement. And the stress and deformation of the tunnel lining are influenced by the parameters of joint sets and in-situ stress, too.

Factors Affecting Efficient Aquifer Restoration at In Situ Uranium Mine Sites

1990 ◽  
Vol 10 (2) ◽  
pp. 107-112 ◽  
Author(s):  
James L. Osiensky ◽  
Roy E. Williams
Keyword(s):  
Uranium Mine ◽  
Factors Affecting ◽  
Mine Sites
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