Effects of experience and familiarity on visual attention and behaviours of bottlenose dolphins (Tursiops truncatus) in presence of humans

Visual attention is an intrinsic part of intra- and inter-specific interactions. Its structure (e.g. short glances vs. long gazes) depends on the species, type and expected outcome of the interaction. The outcomes of earlier repeated interactions determine the resulting valence of the relationships. Human-animal relationships rely upon species-specific cognitive abilities and attentional characteristics for associative learning and memory formation. Visual attention is crucial in cognitive processing and relationships construction, but its structure may depend on species-specific characteristics and relationships' quality. Dolphins are renowned for their cognitive abilities and in human-care settings they have regular interactions with caretakers. Dolphins' visual attention structure and laterality both differ depending on the visual stimulus to which the animal is attending (species-specific, non-biological). We hypothesized that visual attentional characteristics and associated behaviours, in a group of 9 captive bottlenose dolphins (Tursiops truncatus), would differ according to past experience and familiarity with humans. Human motionless tests showed a role of experience (time spent) in the facility on play and vocal production near humans regardless of familiarity. However, familiarity influenced dolphin presence near humans and visual laterality: they stayed longer and used their right eye more to glance at familiar humans. These findings provide new insights on how dolphins cognitively process stimuli according to familiarity and past experiences, as well as on how human - animal relationships evolve in captive settings.