Stream habitat connectivity in the Canadian Arctic: an on-site approach to design and construction

2016 ◽  
Vol 43 (2) ◽  
pp. 139-150 ◽  
Author(s):  
Gregory J. Courtice ◽  
Abul Basar M. Baki ◽  
David Z. Zhu ◽  
Christopher L. Cahill ◽  
William M. Tonn
Keyword(s):  
Adaptive Design ◽  
Fish Habitat ◽  
Canadian Arctic ◽  
Fish Passage ◽  
Headwater Stream ◽  
Habitat Connectivity ◽  
Stream Habitat ◽  
Hydraulic Characteristics ◽  
Habitat Compensation ◽  
Design And Construction

We developed a successful on-site approach for design and construction of stream modifications that addressed challenging remote-site conditions of limited field data and available construction materials. Fish habitat connectivity enhancements were constructed within an Arctic headwater stream containing a naturally impassable cascade section with 13% slope, which was bypassed in a newly constructed channel at 5% slope with nature-like fishpass structures. Primary design considerations included (1) creating suitable hydraulic characteristics for fish passage in periods of high and low discharges; (2) reducing drop heights and creating unimpeded flow paths; (3) improving hydraulic complexity for a variety of stream habitats; and (4) salvaging and incorporating vegetation disturbed from construction activities into riparian and in-stream habitat structures. In high gradient reaches (2.5%–5%), we constructed boulder weirs, boulder chokes, and deflection boulders to overcome migration impediments. In medium gradient reaches (1.5–2.5%), rock ramps, boulder chokes, and deflection boulders were constructed to control hydraulic characteristics to ensure an unimpeded flow path, suitable hydraulic complexity, and resting zones. At lower gradients (<1.5%), we incorporated a softer approach using riparian vegetation and in-stream woody debris to ensure a similar quality of fish habitat as created in the higher gradient reaches. Initial hydraulic responses to the modifications indicated this reconstructed channel provided suitable hydraulic and habitat characteristics for habitat connectivity throughout the entire stream. Our findings advance understanding of headwater stream hydraulics in the Canadian Arctic and will assist in designing future stream restoration and fish habitat compensation projects on small and remote systems. This case study supports the feasibility of successfully constructing future habitat compensation projects in challenging remote environments when using an on-site, adaptive design and construction approach.

Stream modifications to enhance system connectivity for fish habitat compensation: a case study in the Barrenlands region of Canada

2014 ◽  
Vol 41 (7) ◽  
pp. 650-659 ◽  
Author(s):  
Gregory Courtice ◽  
Abul Basar M. Baki ◽  
David Z. Zhu ◽  
Christopher Cahill ◽  
William M. Tonn
Keyword(s):  
Catchment Area ◽  
Rectangular Cross Section ◽  
Fish Habitat ◽  
Fish Passage ◽  
First Year ◽  
Productive Capacity ◽  
Flow Depth ◽  
Lake Catchment ◽  
Habitat Compensation

This study examines stream modification efforts to increase the productive capacity of an isolated system of three small lakes in the Barrenlands region of Arctic Canada by enhancing system connectivity. The lakes’ outlet streams were modified to create conditions favourable for fish passage and thereby promote migration among the lakes and the large lake into which they drain. Gabion step pools (in two streams) and a nature-like choke-and-pool structure (in one stream) were installed. Two years of post-construction hydraulics data were compared to data collected for two years prior to construction to determine the efficacy of the various stream modifications. Initial evaluations indicated unsuccessful performance of gabion step pools, so after the first year, they were retrofitted with boulders to increase flow depth, restrict discharge, improve flow duration, and create unimpeded connections rather than sudden drops. Variation of lake levels and duration, variability, and depth of stream flow indicated that outlet geometry and lake catchment area should be important considerations when enhancing connectivity for fish migration in ephemeral systems. A narrow, rectangular cross-section was deemed effective for increasing flow depth while decreasing discharge, resulting in increased duration of flows. Catchment area was an effective indicator of a headwater lake’s potential response to connectivity enhancements. Smaller catchments may provide inadequate runoff to sustain minimum storage requirements for enhanced connectivity. Our findings should advance the knowledge of headwater system hydraulics in the Barrenlands and assist in designing future fish habitat compensation projects on similar systems.

Restoring stream habitat connectivity: A proposed method for prioritizing the removal of resident fish passage barriers

2013 ◽  
Vol 125 ◽  
pp. 19-27 ◽  
Author(s):  
Jesse R. O'Hanley ◽  
Jed Wright ◽  
Matthew Diebel ◽  
Mark A. Fedora ◽  
Charles L. Soucy
Keyword(s):  
Fish Passage ◽  
Habitat Connectivity ◽  
Stream Habitat ◽  
Resident Fish

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 Analysis for Underwater Sound on Natural River Habitat

2018 ◽  
Vol 40 ◽  
pp. 02047
Author(s):  
Jung-Eun Gu ◽  
Sang Hwa Jung ◽  
Joongu Kang ◽  
Hyoseop Woo
Keyword(s):  
Underwater Acoustics ◽  
Fish Habitat ◽  
Habitat Type ◽  
High Water ◽  
Physical Structure ◽  
Physical Habitat ◽  
Hydraulic Characteristics ◽  
Underwater Sound ◽  
Underwater Acoustic ◽  
Sound Environment

A riffle-pool structure is a representative physical structure of bed in rivers. The change in the physical parameter of the habitat could lead to changes in the sound environment of rivers, which are expressed by underwater acoustics. This change in underwater sound affects fish habitat. In this study, the changes of underwater acoustics were analyzed according to the change of pool-riffle sequence in a natural river. And the correlation between underwater acoustics and hydraulic characteristics was investigated. The survey for underwater acoustics was performed in the Namdae stream where is in Gangwon province. This stream belongs to the Han River basin and the river length is 39.01 km and the catchment area is 127.56 km2. The Namdae stream is a river that accounts for more than 70% of salmon returning to South Korea. The spawning salmon will return to this area around November after growing in the Bering Sea. It is important to manage the fish habitat in this river so there is a lot of research on the enhancement of fish habitat. Hydraulic characteristics were changed by the river bed structure. In this study, we investigated the relationship between underwater acoustic characteristics and hydraulic factors such as riverbed material, flow rate and water depth of each habitat type at 12 sites. The characteristics of underwater acoustic differed relative to different hydraulic factors of the two habitats, which is riffle and pool. The sound pressure level of riffles was relatively higher than that of the pools due to bed materials, shallow depth and high water velocity of riffles. In the future, it is considered that the underwater sound can be utilized as a parameter to evaluate the physical habitat environment of the river.

scholarly journals Importance of considering riparian vegetation requirements for the long-term efficiency of environmental flows in aquatic microhabitats

2017 ◽  
Vol 21 (11) ◽  
pp. 5763-5780 ◽  
Author(s):  
Rui Rivaes ◽  
Isabel Boavida ◽  
José M. Santos ◽  
António N. Pinheiro ◽  
Teresa Ferreira
Keyword(s):  
Fish Species ◽  
Riparian Vegetation ◽  
Environmental Flows ◽  
Fish Habitat ◽  
Natural Habitat ◽  
River Channel ◽  
Habitat Availability ◽  
Hydraulic Characteristics ◽  
Vegetation Development

Abstract. Environmental flows remain biased toward the traditional biological group of fish species. Consequently, these flows ignore the inter-annual flow variability that rules species with longer lifecycles and therefore disregard the long-term perspective of the riverine ecosystem. We analyzed the importance of considering riparian requirements for the long-term efficiency of environmental flows. For that analysis, we modeled the riparian vegetation development for a decade facing different environmental flows in two case studies. Next, we assessed the corresponding fish habitat availability of three common fish species in each of the resulting riparian landscape scenarios. Modeling results demonstrated that the environmental flows disregarding riparian vegetation requirements promoted riparian degradation, particularly vegetation encroachment. Such circumstance altered the hydraulic characteristics of the river channel where flow depths and velocities underwent local changes of up to 10 cm and 40 cm s−1, respectively. Accordingly, after a decade of this flow regime, the available habitat area for the considered fish species experienced modifications of up to 110 % when compared to the natural habitat. In turn, environmental flows regarding riparian vegetation requirements were able to maintain riparian vegetation near natural standards, thereby preserving the hydraulic characteristics of the river channel and sustaining the fish habitat close to the natural condition. As a result, fish habitat availability never changed more than 17 % from the natural habitat.

Design of Steering Gears, Rudders, Rudderstocks, and Propeller Protection for Canadian Arctic Class Vessels

1980 ◽  
Vol 17 (03) ◽  
pp. 267-280
Author(s):  
N. V. Laskey
Keyword(s):  
Pollution Prevention ◽  
Canadian Arctic ◽  
Bulk Carrier ◽  
Arctic Shipping ◽  
Design And Construction

Transport Canada's Arctic Shipping Pollution Prevention Regulations table rules for design and construction of Arctic Class vessels. As Arctic shipping projects have remained moribund for years, some items of equipment described in these rules have not been developed or tested. This paper deals with those items, which are listed in the title, and endeavours to establish their significance and the type of hardware to be developed to implement them. An Appendix is included listing the precise regulations pertaining to the equipment. First 28 000-dwt Arctic Class 2 bulk carrier built to Canadian Arctic Shipping Pollution Prevention Regulations

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