Author: David Cote
Publisher: Halifax : Parks Canada, Atlantic Region
ISBN: 9780662386834
Category : Culverts
Languages : en
Pages : 50

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Book Description

Author: Calvin O. Baker
Publisher:
ISBN:
Category : Culverts
Languages : en
Pages : 84

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Book Description
The success of fish migration through culverts is dependent on the swimming ability of the fish and the hydraulic conditions of the culvert. Properly designed and constructed culverts can minimize the impact on fish passage. Because culverts are typically more economical than bridges, it is appropriate to evaluate when to use culverts and to predict the effects of such culvert installations. During the consideration of alternatives for structures for fish passage, culverts should not be automatically eliminated. This publication has tried to examine the aspects of culvert design and operation relative to the existing information that has been published in previous studies. Ideally, a culvert installation should not change the conditions that existed prior to that installation. This means that the cross-sectional area should not be restricted by the culvert, the slope should not change, and the roughness coefficients should remain the same. Any change in these conditions will result in a velocity change which could alter the sediment transportation capacity of the stream. A truly successful culvert design would include matching the velocities of the fish's swimming zone in the culvert to the swimming capacity of the design fish. Unfortunately, not enough research has been completed to make this an acceptable criterion of culvert design. This approach is preferred because it is easier to reduce the velocities in the swimming zone by increasing the boundary roughness than it is to reduce the mean velocity of the entire culvert. This publication contains some relatively simple guidelines which can reduce the installation problems of culverts in streams containing migrating fish when combined with the expertise of an experience fish biologist, engineer, and hydrologist.

Author: National Fish Passage Program (U.S.)
Publisher:
ISBN:
Category :
Languages : en
Pages : 54

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Book Description

Author: Rachel E. Reagan
Publisher:
ISBN:
Category : Culverts
Languages : en
Pages : 55

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Book Description
Streams across the world are highly fragmented due to the presence of in-stream barriers (e.g., dams and stream-road crossings), many of which restrict or block fish passage. Retrofitting or replacing these structures is a high priority for restoring habitat connectivity for native fishes and other aquatic organisms in the Pacific Northwest. The task of restoring habitat connectivity for problematic stream-road crossings is daunting given the many thousands of barriers that are present and the massive financial investments required. Further, the potential risks to road infrastructure from flooding, debris flows, and climate change will need to be addressed to ensure the best allocation of resources. In this study, I developed and implemented an approach to prioritize culvert replacements by including considerations of fish access, culvert replacement costs, and potential climate change impacts on the risk of culvert failure. The approach described herein involves consideration of expected costs throughout the life-cycle of culverts and an optimization model to select culvert replacements in the context of multiple objectives. I illustrate the application and explore trade-offs in the Siuslaw National Forest, Oregon, a forest with hundreds of stream-road crossings where culvert replacements are being actively carried out. A variety of native fishes are considered, including salmon, trout, sculpin, dace, and lamprey. Within this setting, I applied the road crossing life-cycle and optimization models to prioritize replacements of culverts across a broad landscape and to explore how contrasting management objectives can change our decisions and on-the-ground actions. I found that the selection of culverts for replacement was variable, depending on the replacement costs used, site-specific risk, upstream habitat goals, and species in question. The framework presented here can help to determine which culverts to replace in order to improve connectivity for stream fishes. Evaluating climate change impacts did not change culvert replacement or size selections, but this could be different in areas predicted to have greater climate change impacts.

Author: Chris Riley
Publisher:
ISBN:
Category : Culverts
Languages : en
Pages : 15

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Book Description
This report summarizes the results of a BMP effectiveness monitoring grant study titled: Road Drainage Structure Monitoring of Physical and Biological Characteristics of Fish Passage Through Culverts on Northeast Chichagof Island, Alaska (EPA Grant 104b3). Results from a 1996 Regional Office activity review of Hoonah forest system roads identified the need for additional study on the effects of culvert design and maintenance on upstream fish migration. The objectives of this monitoring project included: 1) Identify physical conditions that impede fish migration at Class I and Class II stream crossings; 2) Sample fish use above and below stream crossings and estimate area of potential habitat loss associated with road related fish migration barriers; and 3) Identify maintenance needs and opportunities for restoring access to fish habitat." -- from the introduction.

Author: G. Michael Fitch
Publisher:
ISBN:
Category : Culverts
Languages : en
Pages : 18

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Book Description
Highway culverts may hinder the normal migrations of various trout species in wild trout streams, due to increased flow velocity, shallow water depths, increased turbulence, and perching. This can impede migrational movements, affecting the genetic diversity and long-term survival of some species. Often, the proper installation of culverts can reduce the adverse effects on fish while maintaining hydraulic efficiency. This study characterized the problems with existing culverts to develop guidelines for the future use of culverts in areas with high gradient streams. Installation criteria will ideally limit the use of bridges where culverts are appropriate, and eliminate the use of culverts where they would create fish passage problems. This will reduce installation, maintenance, and retrofitting costs. The study concluded that culverts can be considered the primary option for crossing trout streams if the following criteria are met: the culvert can be placed on the same slope as that of the streambed the slope of the stream is less than three percent the flow velocity does not exceed 1.2 meters/second under normal flow conditions the barrel of the culvert can be properly countersunk at the outlet to prevent perching. Bridges should be used at these crossings if any of the above criteria cannot be met. Also, baffles should not be used to control streamflow velocities in new culverts, and concrete aprons should not be used at culvert outlets. If culvert bottoms could be cast to have a roughness coefficient equal to that of the streambed, this would allow greater use of culverts at stream crossings without impeding the passage of trout.

Author: Joseph R. Geraci
Publisher: National Aquarium in Baltimore
ISBN: 0977460908
Category : Marine mammals
Languages : en
Pages : 386

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Book Description
Comprehensive manual for understanding and carrying out marine mammal rescue activities for stranded seals, manatees, dolphins, whales, or sea otters.

Author: Hugh Dingle
Publisher: Oxford University Press
ISBN: 0199640386
Category : Science
Languages : en
Pages : 340

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Book Description
Migration, broadly defined as directional movement to take advantage of spatially distributed resources, is a dramatic behaviour and an important component of many life histories that can contribute to the fundamental structuring of ecosystems. In recent years, our understanding of migration has advanced radically with respect to both new data and conceptual understanding. It is now almost twenty years since publication of the first edition, and an authoritative and up-to-date sequel that provides a taxonomically comprehensive overview of the latest research is therefore timely. The emphasis throughout this advanced textbook is on the definition and description of migratory behaviour, its ecological outcomes for individuals, populations, and communities, and how these outcomes lead to natural selection acting on the behaviour to cause its evolution. It takes a truly integrative approach, showing how comparisons across a diversity of organisms and biological disciplines can illuminate migratory life cycles, their evolution, and the relation of migration to other movements. Migration: The Biology of Life on the Move focuses on migration as a behavioural phenomenon with important ecological consequences for organisms as diverse as aphids, butterflies, birds and whales. It is suitable for senior undergraduate and graduate level students taking courses in behaviour, spatial ecology, 'movement ecology', and conservation. It will also be of interest and use to a broader audience of professional ecologists and behaviourists seeking an authoritative overview of this rapidly expanding field.

Author: Richard T. T. Forman
Publisher: Cambridge University Press
ISBN: 1107199131
Category : Nature
Languages : en
Pages : 637

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Book Description
A pioneering book highlighting the dynamic environmental dimensions of towns and villages and spatial connections with surrounding land.

Author: David Lawrence Peterson
Publisher: Columbia University Press
ISBN: 9780231105033
Category : Science
Languages : en
Pages : 638

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Book Description
Ecological Scale provides invaluable perspectives on the application of the concepts of measurement, analysis, and inference in both theoretical and applied ecology, ultimately providing a broad-based understanding for resource managers and other ecological professionals.