Studies have shown that bats are capable of using visual information for a variety of purposes, including navigation and foraging, but the relative contributions of visual and auditory modalities in obstacle avoidance has yet to be fully investigated, particularly in laryngeal echolocating bats. A first step requires a characterization of behavioral responses to different combinations of sensory cues. Here we quantify the behavioral responses of the insectivorous big brown bat, Eptesicus fuscus, in an obstacle avoidance task offering different combinations of auditory and visual cues. To do so, we utilize a new method that eliminates the confounds typically associated with testing bat vision and precludes auditory cues. We find that the presence of visual and auditory cues together enhances bats’ avoidance response to obstacles compared to cues requiring either vision or audition alone. Analysis of flight and echolocation behaviors, such as speed and call rate, did not vary significantly under different obstacle conditions, and thus are not informative indicators of a bat's response to obstacle stimulus type. These findings advance the understanding of the relative importance of visual and auditory sensory modalities in guiding obstacle avoidance behaviors.
Age Specific Behavioral Responses of Odonate Larvae to Chemical and Visual Cues from Predators
