Abstract: A system for the elimination of parasites adhered to fish. The system includes an entry and drainage area configured for the fish with parasites to enter the system, the entry and drainage area joined to an application area through which the fish with parasites pass and come into contact with curtain electrodes and/or grill electrodes. The system includes spray nozzles at least partially housed in the application area and a return chute at least partially situated below the application area to receive and channel the sprayed water. The system also includes a pump that pumps the water to the spray nozzles and an outlet through which the fish without parasites exit the system.

Abstract: Described are various embodiments of an integrated fish diversion system, and lighting device used therein. One embodiment provides a system for diverting approaching fish from a predominant water flow path and toward a bypass. The system comprises a structural diversion assembly to be disposed across the predominant water flow path to guide the approaching fish along the structural diversion assembly to the bypass, while allowing passage of water through the structural diversion assembly along the predominant water flow path. The system further comprises one or more lighting devices to be cooperatively disposed in relation to the structural diversion assembly to further guide the approaching fish toward the bypass; and a controller operatively coupleable to the one or more lighting devices and operable to select an output spectrum thereof to optimize fish guidance thereby.

Abstract: An active indoor location sensing technique is presented for smartphones and other types of mobile devices without requiring any additional sensors or pre-installed infrastructure. The main idea is to actively generate acoustic signatures by transmitting a sound signal with a phone's speakers and sensing its reflections with the phone's microphones. This active sensing achieves finer-grained control of the collected signatures than the widely-used passive sensing.

Abstract: A corral for fish, the corral comprising: at least one wall that defines a pathway along which fish are able to travel wherein the pathway is inwardly winding.

Abstract: Described are various embodiments of an integrated fish diversion system, and lighting device used therein. One embodiment provides a system for diverting approaching fish from a predominant water flow path and toward a bypass. The system comprises a structural diversion assembly to be disposed across the predominant water flow path to guide the approaching fish along the structural diversion assembly to the bypass, while allowing passage of water through the structural diversion assembly along the predominant water flow path. The system further comprises one or more lighting devices to be cooperatively disposed in relation to the structural diversion assembly to further guide the approaching fish toward the bypass; and a controller operatively coupleable to the one or more lighting devices and operable to select an output spectrum thereof to optimize fish guidance thereby.

Abstract: An apparatus for holding back, and diverting, fish in bodies of water by the arrangement of parallel cables (S) braced between two or more abutments (W), wherein the distance between the cables is small enough to prevent fish from swimming through the apparatus.

Abstract: A lice treatment system for marine organisms, such as fish, is described where the system is a closed system comprising: an inlet (1) for fish that shall be treated, a first separator (2) to separate the fish and water and which is arranged after the inlet (1), a pipeline (6) for the transport of the fish, in which, at least, one part of the pipeline (6) constitutes a liquid bath (5) for the fish which is arranged to receive the treatment liquid, a second separator (7) to separate the fish and the treatment liquid, an outlet (8) for the discharge of the treated fish and which is arranged after the second separator (7), and a circulation pump (10) for the circulation of the treatment liquid in the closed system. The part of the pipeline that constitutes the liquid bath (5) is formed in a U-shape so that a liquid bath with respective liquid surfaces (4) is formed.

Abstract: In order to deter underwater animals from an underwater region such as adjacent the entrance to an offtake pipe or channel from a river, sound and light are produced by sound and light producing units in the underwater region and are intermittently pulsed and/or at least one characteristic of the sound and light is repetitively modulated. At least some of the pulses of light and/or the occurrences of at least one feature in at least some of the light modulation repetitions are substantially synchronised with at least some of the pulses of sound and/or the occurrences of at least one feature in at least some of the sound modulation repetitions. For example, the sound may be frequency modulated, and the light may be pulsed when the sound frequency reaches its minimum. It is believed that this synchronisation of light and sound has a synergistic effect.

Abstract: A device to provide a bypass for fish from an upstream reservoir behind a dam, to a lower elevation downstream reservoir. The device employs a flow separation apparatus for separating aquatic life entering the device and communicated to the downstream reservoir, from a portion of fluid flow communicated to the dam intake. The moving fluid within the device creates turbulence to provide a cushioning effect to protect the fish from impacts, while directing water streams to urge fish to an upper portion of the device distant from the water being communicated to the dam in the lower portion.

Abstract: The Weedless Fish Structure is a simple, waterproof, hardened acrylic structure that is submerged in water to provide camouflage and shade cover for game and feeder fish in areas where the body of water does not provide adequate cover. The weights within the main tube allow the apparatus to rest on the bottom with little buoyancy. A small air tube edges around the semi-circular bifurcated shade fin and provides buoyancy to the top fin so it remains upright. Two stakes are provided to secure the apparatus to the bottom when desired to prevent currents from moving the device. If the structure is turned over to where the long tube is above the shade fin, the weights will slide down into the shade fin tube and the air will rise into the long main tube, and then by attaching two floats, the structure becomes a surface apparatus.

Abstract: An Electronic Shark Deterrent provides protection from, and for, sharks and other aquatic creatures. Compact low power circuitry generates high voltage periodic pulse train bursts, disturbing the electroreceptors of the aquatic Elasmobranchi subclass. A train of thirty 33 us 250 Volt (V) electric pulses lasting one second is produced every six seconds. The device is fully portable, requiring no bulky activity impeding buoys, cords, or external power supplies. Advanced circuitry is compact enough to be worn on a watch sized band or attached to garments and recreation or safety equipment. The deterrent can be used in a fixed configuration to protect fish farms and vacation resort swimming areas. It can be affixed to offshore oil rigs and research stations to protect workers. The Electronic Shark Deterrent is compact and portable enough to be used on longlines, trawls and gillnets to reduce the numbers of endangered aquatic creatures unnecessarily destroyed as bycatch.

Abstract: A fish passage system is provided that includes a first weir and a second weir upstream of the first weir. The first and second weirs are each moveable between a deflated condition and an inflated condition. The fish passage system further includes a controller to move the first and second weirs between the inflated and deflated conditions to create at least one pool between the first and second weirs so that fish can migrate upstream and/or downstream of the system without having to jump the first and second weirs.

Abstract: A method for reducing ammonia concentration in an aqueous medium caused by the presence of fish gill/urine discharge, fish faeces and uneaten organic fish-feed particulate matter in recirculating aquaculture tanks. Fish in fish tank water are remotely located or partially isolated from the fish tank water utilized by the sono-molecular-conversion apparatus. Transient cavitation-created, collapsing microsized bubbles generated in the fishless portion of the fish tank water completes ammonia nitrification, mineralization and denitrification therein.

Abstract: A fish-safe screened water diversion apparatus having an input and diverted and non-diverted outputs. Water or other fluid is directed substantially downward under the screen at the input and preferably flows under the screen in a substantially unimpeded manner to the non-diverted output or substantially upwardly and/or diagonally through the screen to the diverted output. Various diversion apparatus and screen embodiments are disclosed.

Abstract: An enclosure, method and apparatus for influencing the swimming behaviour of fish is disclosed. The enclosure defining a space within which the fish can swim, said enclosure having a series of light output members disposed along a path, said light output members being operable to provide a moving visual stimulus along the path by output of light in sequence from the series of light output members thereby to influence the swimming behaviour of the fish.

Abstract: According to one example embodiment, a predator repelling device is installed or placed in or near a water feature that has water-residing species that are vulnerable to predators. The device includes a base member for support and an extension arrangement coupled to and supported by the base member. The extension arrangement extends from the base member above and sufficiently close to the water for repelling predators. The extension arrangement includes an extension portion for providing access to a target location above the water and a motorized portion coupled to the extension portion for controlling the extension arrangement such as by repetitively and automatically sweeping the region surrounding the target location. Accordingly, when a predator attempts to breach the water feature the repetitive movement of the extension arrangement thwarts the predator's attempt and trains the predator to avoid the water feature.

Abstract: A floatable raceway (1) for cultivating fish comprising a partially submersible tank (2) for containing fish having a base (5), opposing sidewalls (6), a gate assembly (8) having removable gates (10, 11) at a water discharge end of the tank (2), and an end wall assembly (7) at a water intake end of the tank (2) having a ramp (9) extending downwardly to the base (5) and towards the gate assembly (8). The raceway (1) also includes floats (3) extending the lengths of the sidewalls (6) for keeping a top of the tank (2) above water level, an airlift assembly (4) connectable to an air supply for introducing oxygenated water to the tank (2) at the water intake end, and a baffle (14) for directing the flow of water through the tank (2) along the base (5). The raceway (1) has a pair of screen gates (10) allowing the movement of fish wastes therethrough and a pair of stop gates (11) for substantially preventing water from discharging from the tank (2).

Abstract: A containment pen for finfish aquaculture, comprising a supporting structure, a net attached to the supporting structure and defining a containment volume for containing finfish, wherein the net comprises a plurality of removable net panels, wherein each of the removable net panels comprises a discrete piece of flexible netting attached along its perimeter to one or more substantially rigid members, and wherein the removable net panels are configured to be removable from the containment pen with the piece of flexible netting remaining attached to the substantially rigid members.

Abstract: A device (10) for repelling selected aquatic creatures, such as sharks. The device consists of an electromagnetic field generator (21, 30) for generating an electromagnetic field (50) that repels sharks and is supported by a buoyant device (20). This provides a shark-free region about the device (10). Multiple devices can be connected together to form an array of repelling devices, thereby extending the shark-free region.

Abstract: A fishladder (10) for use along a waterway includes a channel having a bottom wall (16), a pair of opposing, up-wardly extending sidewalls (18a, b) and opposing open ends. A series of projections (20) are disposed along the channel between the opposing walls (18a, b), and a series of baffles (22) are also disposed along the channel adjacent the series of projections. The baffles (22) define a sheltered side (28), having sheltered areas with a low water flow rate in which fish can rest, and a flow side capable of carrying water having a higher water flow rate and along which fish can advance up the fish ladder. A passage (30) extends through the battles, which allows water to flow through the sheltered areas at a rate capable of preventing the build-up of sediment in the same sheltered areas, but which does not significantly impede the ability of fish to rest in these areas.

Abstract: A structure for diverting fish away from water intakes comprises a porous dike having a bottom portion, a central portion, and a top portion, the top portion preferably being submerged a short distance below the surface, and the central portion having flow passages. In a preferred embodiment, the top and bottom portions comprise solid blocks and the flow passages in the central portion are lined with zebra mussel resistant sleeves to minimize clogging. Preferably the sleeve can be readily replaced as desired.

Abstract: A scalable fish rearing raceway system is provided, incorporating a fish containment structure having two semi-circular end sections, and two or more parallel fish raceways, surrounding a central zone for housing water treatment systems and a secondary fish crop. Heavy particulates are eliminated from the main fish rearing channels by use of conical areas located at either end of the parallel elongated raceways. Continuous removal of dead or dying fish from the raceway is accomplished by means of a floating mortality catcher consisting of a screened ramp at the surface of the cones which continuously collect moribund and dead fish. Grading bars separate and move fish underwater to an adjacent raceway through a common fish transfer channel. This larger scalable fish production system substantially reduces the direct labor and capital costs associated with the production of fish as compared with conventional circular fish rearing tanks.

Abstract: A fish ladder for incorporation between ends of a water structure that includes at least a pair of separate sleeves that are each formed from a puncture resistant flexible material, contain a volume of water and may have a closed end or ends for resting on edge portions of a flat base plate of the fish ladder. The flat base plate includes a pair of parallel spaced apart upstanding side walls that are individually extend across the flat base plate. The upstanding side walls each include pairs of spaced apart channels extending from the side walls, with the pairs align to receive flat rectangular dam sections fitted therein, forming interior dams that a flow of water, as travels through the fish ladder, fills between as pools that fish, traveling up stream, jump between, to travel up the fish ladder and exit into a body of water that is contained by the water structure.

Abstract: A bio-hydraulic testing system is provided for simulating the effect on fish of at least one hydraulic system component. A water flow introduction device introduces a flow of water into the testing system, and a fish introduction means introduces a plurality of fish into the testing system. A flow introduction conduit receives a flow containing water from the flow introduction device and fish from the fish introduction device. A testing module receives the flow from the flow introduction conduit. Monitoring device monitor and record fish activity in the water flow in the testing module. Fish exit the testing module into a flow exit conduit, and are collected by fish collection device located downstream of the exit conduit. Finally, discharge device discharge the water from the testing system.

Abstract: A fish ladder for incorporation between ends of a water structure that includes at least a pair of separate sleeves that are each formed from a puncture resistant flexible material, contain a volume of water and may have a closed end or ends for resting on edge portions of a flat base plate of the fish ladder. The flat base plate includes a pair of parallel spaced apart upstanding side walls that are individually extend across the flat base plate. The upstanding side walls each include pairs of spaced apart channels extending from the side walls, with the pairs align to receive flat rectangular dam sections fitted therein, forming interior dams that a flow of water, as travels through the fish ladder, fills between as pools that fish, traveling up stream, jump between, to travel up the fish ladder and exit into a body of water that is contained by the water structure.

Abstract: A system and method for guiding fish that migrate is provided. A preferred embodiment is affixed to a dam having intakes that: a) generate hydroelectric power and b) serve as a natural hydraulic cue for fish that, once attracted to the intake, may be injured or killed traversing the intake. A device resembling an oversize kitchen exhaust fan hood, with extension, is affixed adjacent the upstream side of a stream barrier that otherwise precludes fish from safely passing. The device simulates a naturally occurring hydraulic cue that fish use to migrate and may be used to defeat competing detrimental hydraulic cues. Also provided are embodiments to enable adjustment of the device to meet changing hydraulic conditions; to preclude the accidental provision of competing negative cues or stimuli; and to complement the simulated natural hydraulic cue provided by the device through using stimuli such as light, sound or combinations thereof.

Abstract: A bypass channel (C) for fish extends along line one side of a river, for the full length of a section of the river in which reservoirs (22, 24, 26, 28) have been created by dams (14, 16, 18, 20). The channel (C) follows the grade of the natural river. It includes an inner wall (34) that varies in height so that it is always higher than the water level in any of the reservoirs. It also includes an outer wall (36) and a bottom wall (38) which are formed on the natural terrain that borders the river and reservoirs. In at least its taller regions, the inner wall (38) may be braced by a diagonal member or a system of member (40). Water flow into the channel (C) maybe regulated by horizontal and/or vertical gates (50, 52) or some other structure for changing the cross sectional area of the channel (C).

Abstract: A method for enhancing or generating a water flow current by the generation of a velocity head differential, to guide fish, including: a venturi eductor to induce higher water pressures; a pump, piping or other motive water source; an adjustable frame to mount the venturi eductor; and a method of using this equipment. Fish may be guided into or away from a waterway area by generating or enhancing a current to guide them. The apparatus may be used as a method to guide fish through low velocity areas of a river, lake, reservoir or other waterway. The apparatus may also be used as a method to create water flow velocities that fish are reluctant to pass through for a barrier or curtain to further guide the fish. The apparatus and method may also be used to transfer temperature-variant water in a waterway.

Abstract: Provided are a device and associated method for simulating natural hydraulic cues received instinctively by waterborne fauna. A preferred embodiment is suitable for modifying existing manmade barriers such as fish diversion screens used at dams. The simulated cues mimic those produced by the flow of water over rough streambeds. Fish detect the cues and avoid contact with the barriers in the same way that they avoid collision with natural features. In one embodiment, a series of rectangular plates are attached to the U-clip connectors on the downstream side of diversion screens. The plates are oriented approximately perpendicular to the flow lines approaching the surface of the screen. The flow contacts the plates and, because the orientation of the plate creates an unstable hydraulic field, the flow alternately slips above and below the plates, creating fluctuating local acceleration zones able to be detected by migrating fish and other waterborne fauna.

Abstract: An apparatus for generating a current to guide fish includes a propeller; a device to rotate the propeller; and a frame to mount the propeller and the device to rotate the propeller. Fish may be guided from an intake area to a fish bypass by generating a current leading away from the intake area. The apparatus may also be used to guide fish through low velocity areas in river situations.

Abstract: The present invention is a safe and effective fish ladder for assisting fish in overcoming dams, especially in the upstream direction. The ladder comprises a series of relatively vertical open pools, which decrease in size in the upstream direction, the pools being conveniently spaced apart a vertical distance which may be easily jumped by the particular fish species of interest. By being arranged relatively vertically, so that the downstream perimeter of one pool is substantially within the downstream perimeter of the pool directly beneath the one pool, the fish ladder does not need to be long and expensive if the dam to overcome is high. Also, by being relatively vertical, the ladder may be conveniently built onto already existing vertical components on the downstream side of a dam, for example, onto the support structure for the discharge flume for downstream migrating fish in the apparatus disclosed in U.S. Pat. No. 5,161,913 (Boylan).

Abstract: A fish-safe screened water diversion apparatus having an input and diverted and non-diverted outputs. Water or other fluid is directed substantially downward under the screen at the input and preferably flows under the screen in a substantially unimpeded manner to the non-diverted output or substantially upwardly and/or diagonally through the screen to the diverted output. Various diversion apparatus and screen embodiments are disclosed.

Abstract: A method and system allowing fish to migrate upstream and downstream, bypassing dams, obstructions, either man-made or natural, safely, freely and in a natural manner. The system consists of a meandering “nature-like” channel constructed of pneumatically placed concrete, shotcrete or gunite that simulates a waterway bed condition. The construction of riffles, ledges, undercut banks and other natural-like features to provide a foundation for the placement of fish habitat, such as gravel beds, boulders, logs, and the like. The placement of sand, gravel, cobbles and such to create and provide an aquatic environment to sustain plant and aquatic life. The introduction of plants and other aquatic life to provide forage, cover and a year around natural-like environment within a river or stream-like migratory bypass channel.

Abstract: A fish ladder is used at a water way outlet of a water way which is higher than a body of water. The fish ladder reduces jump heights for fish entering the water way outlet from the body of water. The fish ladder is a series of tiers installed below and up to the water way outlet, thereby reducing the jump height between the water way outlet and the body of water. The fish ladder is a modular design which can be altered to fit the needs of a particular site based on the size of the body of water, jump height and water way outlet size. The height, length and width of the tiers, as well as the number of tiers, is specific to the site of the installation.

Abstract: A system and method for guiding fish that migrate is provided. A preferred embodiment is affixed to a dam having intakes that: a) generate hydroelectric power and b) serve as a natural hydraulic cue for fish that, once attracted to the intake, are converted to pet food. A device resembling an oversize kitchen exhaust fan hood, with extension, is affixed adjacent the upstream side of a stream barrier that otherwise precludes fish from safely passing. The device simulates a naturally occurring hydraulic cue that fish use to migrate and may be used to defeat competing detrimental hydraulic cues. Also provided are embodiments to enable adjustment of the device to meet changing hydraulic conditions; to preclude the accidental provision of competing negative cues or stimuli; and to complement the simulated natural hydraulic cue provided by the device through using stimuli such as light, sound or combinations thereof.

Abstract: A fishway is disclosed for providing a pathway around obstacles for fish. The fishway is comprised of a pair of spaced fishway walls and a set of weirs located between the fishway walls for dissipating flow energy of water flowing through the fishway. The weirs are disposed in longitudinally spaced relation along the fishway and each consecutive pair of weirs defines a pool between the pair. The weirs are comprised of a center wall, first and second middle walls attached to the center wall on opposite sides of the center wall, and first and second outer walls which are attached at one edge to the first and second middle walls respectively and at the opposite edge to a respective one of the fishway walls. The first and second middle walls form an acute angle facing away from the flow of the water, and each attached middle and outer wall, respectively, form an angle facing towards the flow of the water which is less than 180°.

Abstract: Currently migratory fisheries are impeded in their upstream and downstream movements by one or more dams across rivers. A method and structure is described that overcomes the shortcomings of currently employed methods such as fish ladders, water spilling and barging. A channel of sufficient dimensions to simulate a natural stream bed is employed to parallel the entire length of river and reservoirs and provide passage for the fish. This is accomplished without the breaching and destruction of the dams bypassed.

Abstract: A method of mitigating plankton from fish pens moves denser cleaning water from a selected depth into the pen and discharges it to flow horizontally across the pen, but with a downward component and at a sufficient velocity so that the cleaning water sweeps (carries) the plankton from the pen.

Abstract: A method for enhancing or generating a water flow current by the generation of a velocity head differential, to guide fish, including: a venturi eductor to induce higher water pressures; a pump, piping or other motive water source; an adjustable frame to mount the venturi eductor; and a method of using this equipment. Fish may be guided into or away from a waterway area by generating or enhancing a current to guide them. The apparatus may be used as a method to guide fish through low velocity areas of a river, lake, reservoir or other waterway. The apparatus may also be used as a method to create water flow velocities that fish are reluctant to pass through for a barrier or curtain to further guide the fish. The apparatus and method may also be used to transfer temperature-variant water in a waterway.

Abstract: A substantially transparent separator for separating fish or other aquatic animals within a water-filled display tank is disclosed. The separator divides the tank into multiple, fully viewable regions in fluid communication with each other. The separator comprises at least one transparent, hollow transit chamber, which has opposing mouth openings cut through its surface. Affixed to each of the mouth openings are rigid, substantially vertical divider plates. Apertures through the divider plates adjoin the mouth openings of the transit chamber(s) to form a protected aquatic passageway through the interior of the tank. The separator thus allows groups of physically separated fish or other aquatic animals to swim above, beneath, and beside each other in a three-dimensional manner. Also, each group of aquatic animals has access to the water surface for feeding.

Abstract: Provided are a device and associated method for simulating natural hydraulic cues received instinctively by waterborne fauna. A preferred embodiment is suitable for modifying existing manmade barriers such as fish diversion screens used at dams. The simulated cues mimic those produced by the flow of water over rough streambeds. Fish detect the cues and avoid contact with the barriers in the same way that they avoid collision with natural features. In one embodiment, a series of rectangular plates are attached to the U-clip connectors on the downstream side of diversion screens. The plates are oriented approximately perpendicular to the flow lines approaching the surface of the screen. The flow contacts the plates and, because the orientation of the plate creates an unstable hydraulic field, the flow alternately slips above and below the plates, creating fluctuating local acceleration zones able to be detected by migrating fish and other waterborne fauna.

Abstract: A novel fishway apparatus comprises a channel directed generally above and over a dam or other obstruction, constructed from a plurality of components. Each component incorporates one or more baffles, each baffle having a center passage situated in the center of a dome structure. The fishway extends vertically below the normal elevation of the waterway on both sides of the obstruction, so that the fishway may be flooded by establishing a vacuum in the air pocket formed within the fishway. A well known and commercially available vacuum pump system may be used to establish this vacuum.

Abstract: A method and system allowing fish to migrate upstream and downstream, bypassing dams, obstructions, either man-made or natural, safely, freely and in a natural manner. The system consists of a meandering “nature-like” channel constructed of pneumatically placed concrete, shotcrete or gunite that simulates a waterway bed condition. The construction of riffles, ledges, undercut banks and other natural-like features to provide a foundation for the placement of fish habitat, such as gravel beds, boulders, logs, and the like. The placement of sand, gravel, cobbles and such to create and provide an aquatic environment to sustain plant and aquatic life. The introduction of plants and other aquatic life to provide forage, cover and a year around natural-like environment within a river or stream-like migratory bypass channel.

Abstract: A method of deterring fish from an underwater area includes creating a zone of turbulence along the underwater area, providing a visual deterrence to the fish within the zone, and producing a predefined level of frequency sounds along the zone of turbulence.

Abstract: An adjustable aquarium divider for dividing an aquarium into separate sections while allowing water flow between the sections. The adjustable aquarium divider includes a first panel and a second panel. Each of the panels is rigid and has a first side and second side. Each of the panels has a generally rectangular shape. The panels each have a plurality of apertures therein extending through first and second sides. A fastening member removably fastens the first panel to the second panel such that the first and second panels are partially overlapping and a wall is defined. The first and second panels have aligned upper and lower edges. The wall has a pair of lateral side edges. The panels are positioned in an aquarium such that each of the lateral side edges is abutting one of a pair of opposite walls in the aquarium.

Abstract: A fish diversion apparatus for a water intake of a dam includes a frame extending between a top end oriented towards the water surface and a bottom end oriented below the water surface. The frame supports a number of bar screen panels below the water surface. The bar screen panels allow water flow therethrough from an upstream side to a downstream side. A flow scoop extends from the bottom end of the frame to direct the fish along the upstream face of the bar screen panels. A fish diverter device is provided adjacent the top end of the frame in communication with the upstream side of the bar screen panels.

Abstract: An improved fish deterrent and guide, utilizing generally a paddlewheel (1) consisting of a central shaft (10) with vanes (12) to create a behavioral modifier. When paddlewheel (1) is rotated, the action of the vanes striking the water creates water particle motion (low frequency sound or infrasound), turbulence and current, as well as visual cues that fish avoid. The device is tunable for different fish species and life stages by adjustment of vane style, spacing, and paddlewheel rotation speed. The use of multiple behavioral deterrents creates a measure of reliability in the system. Another advantage is that this fish deterrent provides a continuous lead, which is more effective than typical point-source turbulence and sound generators. Typically, the paddlewheel fish deterrent and guide is positioned at the water surface across the intake to a power plant intake to deter surface oriented downstream migrating fish, and guide them to a bypass.

Abstract: A screened water or fluid diversion having a screen that is disposed in a generally horizontal manner (i.e., more horizontal than vertical, and substantially parallel to the direction of flow over the screen). Various representative embodiments are disclosed. Downstream flow control preferably maintains a head profile or grade line above the level of the screen and a uniform flow transition chamber (UFTC) or like structure is preferably coupled to the screen to facilitate more even and distributed flow through the screen (the diverted flow). In an embodiment that provides safe passage of fish, the grade line is provided sufficiently above the screen to provide safe fish passage. Various screen configurations, downstream flow control, UFTC configurations and other design considerations are disclosed.

Abstract: A system for controlling a hydroelectric power production facility includes sensors for detecting the presence of fish adjacent to the facility. A controller linked to the sensors controls the orientation of control surfaces associated with a turbine/generator set to enhance the survivability of fish entrained into the facility when fish are detected to be present. The controller may instead or in addition activate projection arrays to guide fish to particular turbines or selected areas within the turbines that enhance the survivability of the fish passing through the turbines. The system may also be adapted to control fish bypass and spillway structures within the facility to further enhance the survivability of fish populations. The system balances fish survivability with other parameters related to the operation of the facility, optimizing power production levels once estimates of fish survivability meet targets or optimum levels.

Abstract: A series of disturbed (or rippled) air-water interface regions contiguously arranged guide anadromous fish in a selected direction. Artificial or natural light, diffusely refracted by passage through the disturbed regions, establishes an aura-dominated passage that elicits a learned response from fish which have a “silver underbody” perceive the passage being safe. Accordingly, a fish guidance system in accordance with the present invention may include shower assemblies or nozzles for spraying a fluid, such as water, onto the surface of a body of water, and light assemblies for illuminating disturbed air-water interface regions created by the sprayed fluid. A dark, light absorbing surface beneath the aura-dominated passage enhances its effectiveness as do darkened regions created alongside of and complementing that passage. The darkened regions may also be advantageously exploited for guiding dark, catadromous fish.