Following decades of clearing wood from rivers, the reintroduction of large woody debris is a prominent aquatic habitat restoration technique. Literature suggests that fish are using the structures and an ad hoc set of “lessons learned” in the design of Engineered Log Jams (ELJs) are being amassed and presented at engineering conferences. However, despite the substantial financial investments in this practice, limited knowledge exists around the hydraulics and mechanisms surrounding fish use of ELJs.
To begin investigating the use and benefit of flow field variability around wood for juvenile coho, we conducted a mensurative, 1:1 scale experiment in outdoor stream channels at the Oregon Hatchery Research Center (OHRC) with high-resolution observations of the three-dimensional velocities and fish locations around a full-channel log jam. Hydraulics were characterized around the ELJ using acoustic Doppler velocimetry (ADV) at a spacing of 10 cm. Fish locations in the channel were characterized through use of underwater video. The video, using 3D videogrammetry software, was used to catalog the orientation, length, and three-dimensional movement of individual fish over time and analyzed to define the frequency, duration, and spatial scales of locations occupied by fish around the full-channel jam.
These data were analyzed within the course of this project to investigated questions around: 1) the bioenergetic benefits of wood for minimizing the energy expenditure of juvenile coho in winter, 2) how increasing the resolution of flow field observations impacts estimates of energy expenditure and apparent habitat selection, and 3) detailed and high-resolution observations, modeling, and characterizations of the impacts of large wood on the flow field.
Additional work for this project included characterization of hydraulics with ADVs around a root wad at the OHRC and various field and modelling investigations. Prior to the experiments, topography, velocity, and fish were measured at full-channel (Canal Creek) and meander (Crooked Creek) jam sites. Hydraulics were characterized using acoustic Doppler current profiler (ADCP), and snorkel surveys were performed to observe fish.
|Meander jam on Crooked Creek, a tributary of Fall Creek in the Alsea Basin near Alsea, OR.||Full channel jam on Canal Creek, a tributary of the Alsea River near Tidewater, OR.|
Project Data and Analyses
2D Model Animations
Glass T. 2013. Effects of water velocity and fish length on the shape and size of the foraging areas of juvenile salmonids. Honor’s thesis. Whitman College.
L’Hommedieu W.J. 2015. Effects of an engineered log jam on flow structure and complexity. Master’s Thesis. Oregon State University
Leitshuh A., Walter C., Parisien J., Tullos D. 2014. VidSync Protocol.
Robison D. 2015. Building a better log jam. Oregon’s Agricultural Progress. Oregon State University
Tullos D. and Walter C. 2014. Fish use of turbulence around wood in winter: Physical experiments on hydraulic variability and habitat selection by juvenile coho salmon, Oncorhynchus kisutch. Environmental Biology of Fishes. DOI 10.1007/s10641-014-0362-4
Valverde R.S. 2013. Roughness and geometry effects of engineered log jams on 1-D flow characteristics. Master’s Thesis. Oregon State University
Posters and Presentations
Tullos D. and Walter C. 2013. Linking fish and fluid behavior: Results from a physical model of turbulence and bioenergetics around large wood in rivers. Poster, American Geophysical Union Fall Meeting.
Tullos D. and Walter C. 2014. Linking fish and fluid behavior: Results from a physical model of turbulence and bioenergetics around large wood in rivers. Presentation, River Restoration Northwest Symposium.
Tullos D. and Walter C. 2014. Fish use of turbulence around wood: Habitat variability and selection. Presentation, Oregon State University Monday Morning Meeting, February 3, 2014.
Tullos D., Walter C., and Dunham, J. 2014. Fish use of turbulence around wood: Habitat variability and selection. Presentation, Ecological and Evolutionary Ethology of Fishes meeting.