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Pavlov, D. S., M. A. Skorobogatov and L. G. Shtaf (1982). Influence of degree of stream turbulence on the magnitude of the critical current velocity for fish. Doklady Biological Sciences. 267:560-562.

One of the most important characteristics of a stream is the degree of its turbulence. In fish motion the critical current velocity equals the minimum current velocity that exhausts a fish. In order to increase the range of change in the turbulence intensity in the stream, a system of races was created above the upper net with the help of a submerged hydraulic spring, acting as a generator of elevated turbulence. Young roach were used in the study. A stream with a higher degree of turbulence possesses a greater kinetic energy for fish. Therefore, the energy expenditures of fish will be higher in such currents, leading to a decline in the critical current velocity. The findings should be taken into account in the control of fish behavior. An increase in the degree of turbulence in active fishing equipment, such as a trawler, will promote the most rapid exhaustion of the fish and an increase in the catch. At the same time an increased stream turbulence in the fish tanks of fish-passing structures is undesirable as it will result in the loss of fish to the current.