Effects of noise on growth and reproduction of Crangon crangon in rearing tanks

Brown shrimp, Crangon crangon (L.), were reared in Angoulins, France from April to June 1981. Rearing in a soundproof box reproduced acoustical conditions similar to those prevailing in the shrimps' original environment. Growth and reproduction were compared to those of shrimp from the same source but reared in acoustical conditions prevailing in a thermoregulated aquarium; other experimental conditions were identical. In the aquarium, the noise-level attained 30 dB in the 25 to 400 Hz frequency range; this permanently high sound-level resulted in a significant reduction in growth and reproduction rates of the shrimp. To a lesser degree, noise also appears to increase aggression (cannibalism) and mortality rate and to decrease food uptake. These symptoms are extremely similar to those induced by adaptation to stress.