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R.W. Jay Lacey

Publications and source records attributed to R.W. Jay Lacey.

4 recordsLinked to original sources

Effects of turbulence-inducing baffles on passage performance of brook trout, white sucker, and sea lamprey: Implications for conservation and control

Invasive sea lamprey ( Petromyzon marinus ) control in the Great Lakes is ongoing. Installing passive selective passage structures could reduce costs, yet there is a need to evaluate such methods under realistic hydraulic conditions to inform designs. In this study, we evaluated the swimming performance of brook trout ( Salvelinus fontinalis ), white sucker ( Catostomus commersonii ), and sea lamprey under manipulated flows and baffle configurations in a 35 m flume lined with substrate preventing attachment. Using accelerated failure time models, we examined ascent distance (Dmax) under two slopes (1% and 3%) and velocities from 0.25–3.0 m s⁻¹. Responses varied by species: white sucker had the greatest Dmax, especially at 1% slope, whereas sea lamprey, despite lacking paired fins/rays, occasionally exceeded white sucker at 3% with small spoiler baffles and bare substrate. Contrary to common perception, brook trout, the only salmonid in this study, performed less well than the other two species. Across species, higher velocities impaired performance, with declines linked to energy dissipation (EDF). Findings show how hydraulic structures shape species-specific passage.

Great Lakes↗

Sediment infilling benefits rainbow trout passage in a baffled channel

Fish are thought to exploit low velocity recirculation zones in the wakes of baffles to take refuge from challenging hydraulic conditions in baffled culverts. Here, we investigate how sediment deposition in the wakes of baffles affects passage and behaviors of juvenile rainbow trout in a baffled experimental flume. High temporal resolution 3D fish tracking provided detailed kinematics of adopted trajectories. Stereoscopic particle image velocimetry permitted a finely resolved description of the flow over a clear baffle configuration and the same configuration with sediment wedges placed in their wakes. Controlled station-holding, suggestive of flow-refuging, only occurred when sediment wedges were blocking the baffles’ recirculation region. Also, maximum distances of ascent were higher, and slower ground-speeds were employed in the sediment condition. The results of this study suggest the turbulent recirculatory wakes of the clear bed condition caused postural instabilities and were in many ways detrimental to passage performance. Additional research is required to understand the relationships existing between baffle height, hydrodynamic recirculatory wake metrics, sediment deposition and the behavioral responses of fish interacting with weir baffle wakes.

Ecological Engineering↗

Influence of baffles on upstream passage of brook trout and brown trout in an experimental box culvert

There is much to learn about improving baffle designs to increase successful fish passage through culverts. A fish’s motivation to attempt entry into the culvert is essential. Upon entry, successful passage will largely depend on the physiological ability of the fish to navigate the entire culvert length. In this study, the motivation of brook trout ( Salvelinus fontinalis (Mitchill, 1814)) and brown trout ( Salmo trutta Linnaeus, 1758) to attempt ascent of an experimental flume, which mimics a roadway culvert left bare (smooth) or fitted with either spoiler or weir baffles, is assessed. Performance, measured as maximum distance of ascent within the flume, is also quantified. The bare flume was the most motivating for brook trout, and the weirs were most motivating for brown trout. As a rule, brown trout showed less motivation to stage attempts than brook trout, except within the weir baffle treatments. Performance was greatest in the weirs for smaller trout and in the spoiler baffles for larger trout. Our findings suggest that baffle form influences passage rates at road crossings in ways previously unknown and further stresses the importance of considering fish motivation and performance together when assessing the efficacy of baffle forms.

Canadian Journal of Fisheries and Aquatic Sciences↗

The effects of horizontally and vertically oriented baffles on flow structure andascent performance of upstream-migrating fish

Considerable effort has been expended to construct culverts and fishways that allow for fish passage. However, the designs have seldom considered behaviour, energetics, and biomechanics of fish. In this study, we performed controlled experiments, in which upstreammigrating Alewife (Alosa pseudoharengus) and Brook Trout (Salvelinus fontinalis) were allowed to volitionally enter either one of two open channels. These channels were outfitted with horizontally and vertically oriented baffles. The flow structure was characterized using acoustic Doppler velocimeter measurements. The added baffles had a marked influence on the flow field, which was distinct between horizontal and vertical baffles, indicative of horizontally and vertically orientated vortices, respectively. Passage success was measured, both in terms of attraction and ascent performance under each flow condition. The results indicated that Alewife and Brook Trout staged significantly more attempts into the vertical baffled channel compared to the horizontal baffled channel. However, Alewife traversed greater distances swimming in the channel with the horizontal baffles at the lower flow condition. Brook Trout also swam further under low flow but traversed similar dtistances in both channels. This information furthers our understanding of both ascent performance and behavioural responses of fish in relation to turbulent flow and roughness orientation.

Journal of Ecohydraulics↗