Abstract
Adult Pacific salmon (Oncorhynchus spp.) in the Fraser River, British Columbia, can die trying to retrace and ascend the river network to their natal spawning grounds due to hydraulic barriers, where encounter velocities exceed swim speeds of adult salmon. We evaluated river hydraulics, river morphology, and swimming ability to better understand these potential hydraulic barriers. A 375 km centerline velocity survey of the Fraser Canyon identified 22 high velocity locations where the distribution of velocity within the reach could produce a hydraulic barrier. We identified and studied three flow types associated with these 22 high velocity locations: 1) plunging flows, 2) rapids, and 3) overfalls, using drone footage at various discharges to examine flow structure and compare surface velocities with swimming modes. Complex flow within the major hydraulic features highlight the spatial locations requiring anaerobic swimming and areas of potential recovery that change with discharge. This approach can be used to improve the understanding of fish migration limits in a natural river system and aid in future mitigation.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Canadian Journal of Fisheries and Aquatic Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
