Displacement pattern of marine shrimp Litopenaeus vannamel (Boone, 1931) (Crustacea, Decapoda, Penaeidae) in light and dark phases during a 24-hour period.

Litopenaeus vannamei (Boone, 1931) daily behavior pattern is still poorly understood. With the aim of optimizing the management of shrimp farms through the Study of this animal behavior, experiments were performed with juvenile (7.57 +/- 1.01), which were marked and kept in aquariums (301). To record activity, the aquariums were Submitted to an artificial photoperiod (light and dark phases, 12h:12h), with 16 shrimp (33 m(2)) monitored in each phase for 20 days, for 15-minute periods every hour. Food was provided at random times and a record kept of horizontal and vertical displacement (continuous focal), swimming and exploration behavior (instantaneous focal). The horizontal and vertical displacements of the shrimp were greater during the dark phase, with a predominance of the swimming behavior. Exploration of the Substrate Occurred in both phases, with a peak between five and seven hours after the lights were turned on.