Validation of a novel fully immersive Virtual Reality setup with a behavioural study of freely-moving fish

Abstract

AbstractVirtual Reality (VR) enables standardised stimuli to invoke behavioural responses in animals, however, in fish studies VR has been limited to either basic 2D visual stimuli for freely-moving individuals or simple 3D stimuli for head-restrained individuals. We developed a novel fully immersive VR setup with 3D scenarios, validated in a proof of concept study on the behaviour of coral reef post-larvae. Larval fish use a variety of cues to select a habitat during recruitment, and to recognize conspecifics and predators, but which visual cues are used remains unknown. We measured behavioural responses of groups of five convict surgeonfish (Acanthurus triostegus) to simulations of habitats, static or moving shoals of conspecifics, predators, and non-aggressive heterospecifics. Post-larvae were consistently attracted to virtual corals and conspecifics, but repulsed by their predators. Post-larvae also discriminated between species of similar sizes: they were attracted more to conspecifics than butterflyfish, and repulsed more by predators than parrotfish. The quality of visual simulations was high enough to identify between visual cues – size, body shape, colour pattern – used by post-larval fish in species recognition. Our VR and tracking technologies offer new possibilities to investigate fish behaviour through the quantitative analysis of their physical reactions to highly-controlled scenarios.