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 improved fish deterrent and guide utilizing generally a pneumatic oscillator (1) and oscillated plate (9), to generate water particle motion (low frequency sound or infrasound) and specifically water particle accelerations to which fish exhibit an avoidance response. The invention is reliable, reasonably portable and deployable, low-maintenance, and tunable to produce the desired water particle motion. Reliability is due to the piston (4) being cushioned by air at the end of each stroke and redirected without impacting the casing. The operation of the apparatus is easily verified from the water surface by inspection of the backpressure regulator (13). The apparatus is tunable through adjustment of the inlet pressure, backpressure, and size, shape, and mass of the oscillated plate.

Abstract: A means and method for transporting fish from a lower body of water to a higher body of water. The means comprises a tubular lock with a gated entrance below the level of the lower body of water through which fish may enter the lock and a discharge passage above the level of the upper body of water. The fish raising means in the lock is a crowder pulled upward by a surface float as water from the upper body of water gravitationally flows into the closed lock filling it to the level of the upper body. Water is then pumped into the lock to raise the level to the discharge passage. The crowder is then caused to float upward the remaining distance through the water to the level of the discharge passage by the introduction of air into a pocket on the underside of the crowder. The fish are then automatically discharged from the lock into the discharge passage by the out of water position of the crowder.