Multimodal mixed messages: the use of multiple cues allows greater accuracy in social recognition and predator detection decisions in the mosquitofish, Gambusia holbrooki

Information gathered by animals through different sensory modalities at any given point may be aligned, that is, consistent across different senses, or in conflict, where different senses provide different information. This latter instance may occur for a variety of reasons, including differences in speed of dispersal and persistence of some cues relative to others. By gathering information using multiple sensory modalities simultaneously, animals may be able to mediate this conflict and increase decision accuracy. This study examined the use of different sensory modalities over a short spatial range by mosquitofish in locating conspecifics and avoiding a cryptic sympatric predator. Fish were provided with visual and/or chemical cues either separately or simultaneously. Where visual and chemical cues were provided simultaneously, they were either aligned or in conflict. As expected, fish with access to aligned cues generally performed best, approaching a conspecific shoal sooner and spending longer in proximity to the shoal and avoiding approaching the predators for longer and spending less time in proximity to them. Fish with access to conflicting cues performed as well as those with access to aligned cues in overall time spent in proximity to predators, while they were more wary of conspecific visual cues presented in association with predator chemical cues. However, fish with access to conflicting cues were slower to approach conspecific visual cues and, crucially, faster to approach predator visual cues than fish with access to aligned cues. This suggests that although multimodal cue use generally promotes accuracy, the potential remains for conflicting cues to generate risky decisions.