Conditioning as an aid to fish harvest

Abstract

This paper presents an instrumental learning technique which may be used to concentrate fish in a small area of an aquaculture pond with the purpose of harvesting. An acoustic discriminative stimulus, followed by a food reinforcer was administered in a regular, automated sequence, in a particular location. Observation of the number of fish present in the fishing area was achieved by a standard video-camera and a monitor; therefore, timing of the stimuli and netting could be adjusted. Monitoring of the fishing area during training is important in order to determine the instant of maximum gathering of the fish at the location of the stimuli. In the present conditions the optimum time for harvest was at 12 days of training and at 4–6 s after the acoustic stimulus began. This technique may be an important aid for harvesting in farms.