Advances in Fisheries Bioengineering

Abstract.—Aquatic Filter Barrier (AFB) is a permeable fabric material used to reduce the entrainment of ichthyoplankton at water intakes. To determine the potential for this material to protect a wide range of species, we evaluated the retention and survival of the early life stages of common carp <em>Cyprinus carpio</em>, rainbow smelt <em>Osmerus mordax</em>, white sucker <em>Catostomus commersonii</em>, striped bass <em>Morone saxatilis</em>, and bluegill <em>Lepomis macrochirus </em>exposed to AFB fabric in the laboratory. Twelve flow-through testing apparatuses were used in a closed-loop system to evaluate two flow rates (0.04 L/min/cm2) and 0.08 L/min/cm2) and three sizes of fabric perforation (0.5, 1.0, and 1.5 mm) with each species. The results indicate that, with one exception (pair-wise comparison of bluegill survival between 1.0-mm and 1.5- mm perforations; <em>p </em>= 0.0481), survival of organisms was not significantly correlated (<em>p </em>≤ 0.05) to either flow rate or perforation size. Retention of organisms decreased significantly with increasing flow rate for one species of fish (pair-wise comparison of rainbow smelt between 0.04 and 0.08 L/min/cm²; <em>p </em>= 0.0084). In addition, larger perforation sizes resulted in significant decreases in retention for three of the test species (common carp, rainbow smelt, and striped bass; <em>p </em>≤ 0.05). Consequently, the potential effectiveness AFB material is reduced by the use of larger perforation sizes. Provided that the material can be maintained and perforation sizes remain small (0.5 mm), AFB should prevent the entrainment of the majority of the organisms of the species tested in the laboratory.

Advances in Fisheries Bioengineering

<em>Abstract.</em>—Although many hydroelectric dams have fishways for upstream passage of migratory fish, passage delays often occur at these sites. Migrational delay may affect fish detrimentally in several ways, including depletion of energy reserves, suboptimal arrival timing at spawning sites, and prolonged exposure to hazardous conditions at the face of dams. We applied time-to-event analyses to passage times of radio-tagged adult Chinook salmon <em>Oncorhynchus tshawytscha </em>at four dams on the lower Columbia River, where many fish require several days to pass each dam. The analysis allowed us to determine instantaneous passage rates in response to fluctuating river conditions. By relating variability in passage rate to the predictor variables river temperature, river flow, and fish size, we determined the relative contribution of various factors to the passage time of migrating fish. We fit the model by maximizing the likelihood function that incorporated information from individuals rather than aggregated groups of fish. We used Akaike’s Information Criterion to distinguish among several competing models, each of which used a different predictor variable. We found that daytime passage rates were significantly greater than nighttime passage rates. Also, the influence of river flow, river temperature, and fish length on passage rates varied at the four dams. However, when a factor had a significant influence on passage time, the direction of the relationship was consistent across dams: river flow and fish length were positively related to passage time (greater values led to longer passage time), and river temperature was negatively related. This method is easily adaptable to study passage time of any fish population facing a broad range of obstacles to migration, whether natural or man-made.

Advances in Fisheries Bioengineering

<em>Abstract</em>.—Fish ladder designs that pass adult sturgeons are poorly studied. This is partly due to difficulties associated with obtaining and testing large adults. To learn about behavior and swimming of sturgeons in fish ladder environments, we observed juvenile lake sturgeon <em>Acipenser fulvescens </em>to determine the type of ladder opening that fish passed best. We also constructed a short fish ladder (6% slope) using the best opening type and determined the general usefulness of the ladder design to pass juvenile lake sturgeon, pallid sturgeon <em>Scaphirhynchus albus </em>and shovelnose sturgeon <EM>S</EM>. <em>platorynchus</em>. Lake sturgeon swam upstream through orifice and vertical openings better than through surface weir or weir and orifice openings. Because 37% of the fish hit the orifice when swimming upstream, and also, sturgeon could be damaged passing downstream through an orifice, we focused on testing a ladder design with vertical openings. A side-baffle ladder design that created vertical openings that alternated from side to side showed promise at passing the three species of sturgeons. All lake sturgeons (<EM>N </EM>= 15), most pallid sturgeons (12 of 22 fish, 55%), and 1 of 3 shovelnose sturgeons ascended the side-baffle design. Also, all sturgeon species moved safely downstream in the side-baffle ladder by passively drifting tail-first. Mean velocity in side-baffle openings was 60–75 cm/s, so sturgeons could use prolonged swimming speed to swim upstream. Vertical openings were wide enough for fish to partially erect their pectoral fins, likely a critical factor for maintaining balance. Our observations suggest that a ladder for adults should have vertical openings, enable fish to swim continuously and not stop at cross-channel barriers, have resting areas, enable fish to safely drift downstream, and enable fish to swim upstream using prolonged swim speed. The study of juvenile sturgeon behavior and swimming ability can contribute to developing a fish ladder for adults. This approach to fish ladder development can be used for other species with large adults.

Advances in Fisheries Bioengineering

<em>Abstract.</em>—The results of our study contradict the current view that postspawned or late running adult American shad <em>Alosa sapidissima </em>suffer higher turbine-related mortality, particularly at water temperatures ≥ 20.0°C, than prespawned upstream migrants. The reported difficulty in successfully tagging postspawned American shad led us to fabricate a specialized stress reduction device to minimize handling and tagging related mortality; such losses were essentially zero in our turbine passage survival experiment. Our methodology may be broadly applicable to other large-sized fish (>350 mm) or fragile species for estimating postpassage in-river survival. We successfully noted the postpassage condition and injury type of virtually all recaptured fish, removed balloon tags, and released shad with radio tags attached to estimate postpassage in-river survival. The estimated 24–48 h, post-passage, inriver survival through Kaplan and mixed-flow turbines was 88.2% (90% confidence interval [CI] = 82.5–94.0%) and 84.3% (90% CI = 77.9–90.6%), respectively. These estimates are higher than the only two literature citations (53% and 75.8%) found for healthy prespawned shad passed through similar type turbines. Mathematical projections of potential American shad population responses show that a reduction in repeat spawners of the magnitude estimated herein has a minor effect on the time to achieve a self-sustaining population in the upper Susquehanna River relative to the effects of reductions in fishway passage efficiency (<80%) at each dam and low reproductive rates (indexed by returning adults after accounting for mortality from all sources). However, it appears that the American shad population can increase downstream of the first dam on the river.

Advances in Fisheries Bioengineering

Abstract.—A water filtration and ozonation system was recently installed to treat creek water used to culture species of concern at the U.S. Fish and Wildlife Service’s Northeast Fishery Center, Lamar National Fish Hatchery (NFH). Past experience with fish culture indicates that the following bacterial pathogens are endemic to the creek water supply: <em>Aeromonas salmonicida</em>, <em>Yersinia ruckeri</em>, <em>Flavobacterium columnaris</em>, and <em>Flavobacterium psychrophilia</em>. Water samples were collected from sites located before and after filtration and ozonation and examined for culturable bacteria. Variable operation of the filtration/ozonation system was used to examine (1) the effect of microscreen filtration (i.e., using drum filters containing 37-μm sieve panels) on ozone inactivation of bacterial microorganisms, (2) the effect of dissolved ozone contact times on inactivation of bacterial microorganisms, and (3) the effect of water quality fluctuations on the dissolved ozone demand measured during the course of these tests. Inactivation exceeded 98% for all bacteria when ozone <em>C*t </em>values were about 1.0 and reached 100% at 21.3, regardless of water quality parameters or implementation of microscreen filtration. These results indicate that the use of ozonation to treat surface water supplies used for fish culture facilities will effectively inactivate the majority of bacteria entering the system and will likely serve to prevent introduction of bacteria that can be pathogenic to fish.

Advances in Fisheries Bioengineering

Abstract.—Surface flow bypass (SFB) concept was evaluated by the Portland District Corps of Engineers to increase survival of emigrant juvenile salmonids passing hydroelectric facilities on the lower Columbia and Snake rivers. Although surface oriented flow had shown promise as efficient juvenile salmonid passage routes, fish behavioral and engineering criteria were lacking to ensure that the most promising prototypes could be evaluated. Surface-oriented sluiceways have long been known to pass a high percentage of juvenile salmonids per the volume of water passed. Also, the Wells Project on the mid-Columbia River had shown great success with deep-slot entrances. A bioengineering evaluation conducted by the Portland District Corps of Engineers and their contractors determined that a stand-alone deep-slot SFB would be the best alternative (alternative A) to evaluate at Bonneville first powerhouse. However, testing the concept of alternative A would be cost prohibitive from a standpoint of handling the flow. So, the prototype surface collector (PSC) was constructed as a “test box” in order to alter the hydraulic environment as drastically as possible to best evaluate the deep slot concept. Hydraulic evaluations consisted of physical hydraulics using a 1:25 powerhouse sectional model, a 1:55 powerhouse forebay model, and prototype hydraulics. Biological evaluations consisted of behavioral data from multibeam and split-beam hydroacoustics, threedimensional acoustic telemetry, and radio telemetry. Efficiency evaluations consisted of radio telemetry and fixed hydroacoustics. The PSC provided positive results for the deep-slot concept, although we cannot report that we broke the salmonid “behavioral code.” Collection efficiency was determined to be 83% for steelhead <em>Oncorhynchus mykiss</em>, 79% for yearling Chinook salmon <em>O. tshawytscha</em>, and 84% for subyearling Chinook salmon. Three years of investigations indicate that the PSC was a well-designed prototype that provided a thorough evaluation of the SFB deep slot concept. The only shortfall from a biological stand point was that the ramp associated with alternative A and associated fish passage was not evaluated. The only shortfall from an engineering stand point was that the lost turbine efficiency due to the turbine intake blockage was not evaluated.

Advances in Fisheries Bioengineering

<em>Abstract</em>.—A 2-year experiment was conducted on the Ariège River (southwest France) to assess effectiveness of downstream fish passage facilities for Atlantic salmon <em>Salmo salar </em>smolts at four consecutive small hydroelectric plants located on a diversion structure. The efficiency of these bypasses, evaluated using passive integrated transponder (PIT) telemetry, varied significantly between sites. The highest efficiency (greater than 65%) was obtained with two entirely new downstream passage facilities, whereas less than 40% of PIT-tagged smolts migrated through two other bypasses that were simple retrofits of existing trash sluices. Performances of two bypasses were significantly improved using either a submerged horizontal screen designed to limit upwelling or mercury lights at the bypass entrance. At two sites, a difference in fish size was also observed between smolts using the bypasses and those passing through the conventional intake trash racks, with larger fish using the bypass and smaller fish being entrained through the turbine intake. It was also demonstrated that the probability for spillway passage by tagged fish increased with increases in the proportion of total river discharge spilling and with decreases in fish size. The results of this study demonstrate how different parameters can influence downstream bypass efficiencies and provide information on how downstream passage for migratory fish can be improved at small hydropower projects.

Advances in Fisheries Bioengineering

Abstract<em>.</em>—The vertical slot fishway (VSF) is a hydraulic structure used to aid in the passage of fish past barriers to their natural migration. These barriers may consist of such structures as weirs, dams, culverts, and tidal barrages.

Advances in Fisheries Bioengineering

<em>Abstract.</em>—Historically, spillways and sluiceways at hydroelectric dams were constructed as conduits for transporting excess river flow or debris with little focus on their potential for safe fish passage routes. In recent times, however, these conveyances are increasingly viewed as viable fish passage routes and are used to increase potential survival for the declining salmonid populations, particularly in the Pacific Northwest. However, spill is uneconomical and, with some spillway configurations, may cause potentially lethal levels of total dissolved gas (TDG) saturation in the river. Recent estimates (direct effects) of juvenile anadromous fish survival and condition after passing nonturbine exit routes at hydro dams have shown much variation (83–100% survival) depending upon site-specific hydraulic characteristics, trajectory of entrained fish, and obstructions in the flow path. Efforts are underway to modify spillways and bypasses at several hydroelectric dams to decrease TDG and eliminate and/or minimize fish injury.