Download the full-sized PDF of Assessing Responses of Fish to Habitat Enhancement in Barrenlands Streams, N.W.T., CanadaDownload the full-sized PDF



Permanent link (DOI):


Export to: EndNote  |  Zotero  |  Mendeley


This file is in the following communities:

Graduate Studies and Research, Faculty of


This file is in the following collections:

Theses and Dissertations

Assessing Responses of Fish to Habitat Enhancement in Barrenlands Streams, N.W.T., Canada Open Access


Other title
Diel Periodicity
Fisheries Act
Whole Ecosystem Manipulation
Fish Habitat Enhancement
Arctic Grayling
Gabion-style Fishpass
Nature-like Fishpass
Adaptive Management
Habitat Selection
Type of item
Degree grantor
University of Alberta
Author or creator
Cahill, Christopher L
Supervisor and department
Tonn, William M (Biological Sciences), Howland, Kimberly (Biological Sciences)
Examining committee member and department
Tierney, Keith (Biological Sciences)
Bayne, Erin (Biological Sciences)
Davis, Corey (Biological Sciences)
Department of Biological Sciences
Date accepted
Graduation date
Master of Science
Degree level
The development of the Diavik diamond mine destroyed pristine lakes and streams in Barrenlands region of northern Canada. Subsequently, several fish habitat compensation projects were undertaken to offset these losses. The M-Lakes project was intended to enhance the productive capacity of a pristine headwater lake-stream system through improved stream channel connectivity among three small (<5 ha), isolated lakes and with the much larger (>57,000 ha) Lac de Gras. Three fishpasses (two gabion-style pool-weir and one nature-like choke-pool) were constructed to enhance inter-lake connectivity in the M-Lakes system. My objectives were to determine if (1) fish ≥ 150 mm were attracted to and passed through fishpasses, (2) fish use of fishpasses was comparable to reference streams before and after construction and to manipulated streams before construction, and to (3) identify environmental correlates to fish passage events when fishpasses allowed for fish movement. I used passive integrated transponder telemetry, and visual and electrofishing surveys to address my objectives for one year before (2011) and two years after fishpass construction (2012-2013). The gabion-style fishpasses limited fish movement and use, while the nature-like fishpass allowed for fish movement and use comparable to reference streams and the stream prior to manipulation. Few consistent correlates with hydraulic conditions and date were identified for passage events of Arctic Grayling (Thymallus arcticus) in the nature-like fishpass, relative to the conditions available. However, I observed strong diel periodicity in Arctic Grayling passage activity as most (95%; 137/144) passage events occurred during evening or early morning (18:00-5:59). My findings provide evidence against using gabion-style pool-weir fishpasses in low-gradient headwater Barrenlands streams, and demonstrate that nature-like fishpasses can be effective tools for enhancing connectivity in these systems. Additionally, this thesis documents the first case of clear diel periodicity in passage activity for Arctic Grayling, which may be a response to avian predation given the shallow depth of the fishpass.
Permission is hereby granted to the University of Alberta Libraries to reproduce single copies of this thesis and to lend or sell such copies for private, scholarly or scientific research purposes only. Where the thesis is converted to, or otherwise made available in digital form, the University of Alberta will advise potential users of the thesis of these terms. The author reserves all other publication and other rights in association with the copyright in the thesis and, except as herein before provided, neither the thesis nor any substantial portion thereof may be printed or otherwise reproduced in any material form whatsoever without the author's prior written permission.
Citation for previous publication

File Details

Date Uploaded
Date Modified
Audit Status
Audits have not yet been run on this file.
File format: pdf (PDF/A)
Mime type: application/pdf
File size: 2616471
Last modified: 2015:10:12 20:49:54-06:00
Filename: Cahill_Christopher_L_201409_MSc.pdf
Original checksum: d8c90e7a10a18da43b93438e482bb877
Activity of users you follow
User Activity Date