Next Article in Journal
Critical Transitions in Lake Ecosystem State May Be Driven by Coupled Feedback Mechanisms: A Case Study from Lake Erhai, China
Previous Article in Journal
Effect of Hydraulic Retention Time on the Performance of a Compact Moving Bed Biofilm Reactor for Effluent Polishing of Treated Sewage
Article

Effects of In-Channel Structure on Chinook Salmon Spawning Habitat and Embryo Production

1
California Department of Fish and Wildlife, West Sacramento, CA 95605, USA
2
Department of Watershed Sciences, Utah State University, Logan, UT 84322, USA
3
Cramer Fish Sciences, River Science and Restoration Lab., West Sacramento, CA 95691, USA
4
Department of Ecology & Evolutionary Biology, University of California, Santa Cruz, CA 95060, USA
*
Author to whom correspondence should be addressed.
Academic Editor: Matthew McBroom
Water 2022, 14(1), 83; https://doi.org/10.3390/w14010083
Received: 24 November 2021 / Revised: 29 December 2021 / Accepted: 30 December 2021 / Published: 3 January 2022
Adult salmonids are frequently observed building redds adjacent to in-channel structure, including boulders and large woody debris. These areas are thought to be preferentially selected for a variety of reasons, including energy and/or predation refugia for spawners, and increased hyporheic exchange for incubating embryos. This research sought to quantify in-channel structure effects on local hydraulics and hyporheic flow and provide a mechanistic link between these changes and the survival, development, and growth of Chinook salmon Oncorhynchus tshawytscha embryos. Data were collected in an eight-kilometer reach, on the regulated lower Mokelumne River, in the California Central Valley. Nine paired sites, consisting of an area containing in-channel structure paired with an adjacent area lacking in-channel structure, were evaluated. Results indicated that in-channel structure disrupts surface water velocity patterns, creating pressure differences that significantly increase vertical hydraulic gradients within the subsurface. Overall, in-channel structure did not significantly increase survival, development, and growth of Chinook salmon embryos. However, at several low gradient downstream sites containing in-channel structure, embryo survival, development, and growth were significantly higher relative to paired sites lacking such features. Preliminary data indicate that adding or maintaining in-channel structure, including woody material, in suboptimal spawning reaches improves the incubation environment for salmonid embryos in regulated reaches of a lowland stream. More research examining temporal variation and a full range of incubation depths is needed to further assess these findings. View Full-Text
Keywords: in-channel structure; large woody debris; vertical hydraulic gradient; Chinook salmon; spawning habitat; embryo production; California Central Valley in-channel structure; large woody debris; vertical hydraulic gradient; Chinook salmon; spawning habitat; embryo production; California Central Valley
Show Figures

Figure 1

MDPI and ACS Style

Bilski, R.L.; Wheaton, J.M.; Merz, J.E. Effects of In-Channel Structure on Chinook Salmon Spawning Habitat and Embryo Production. Water 2022, 14, 83. https://doi.org/10.3390/w14010083

AMA Style

Bilski RL, Wheaton JM, Merz JE. Effects of In-Channel Structure on Chinook Salmon Spawning Habitat and Embryo Production. Water. 2022; 14(1):83. https://doi.org/10.3390/w14010083

Chicago/Turabian Style

Bilski, Robyn L., Joseph M. Wheaton, and Joseph E. Merz. 2022. "Effects of In-Channel Structure on Chinook Salmon Spawning Habitat and Embryo Production" Water 14, no. 1: 83. https://doi.org/10.3390/w14010083

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop