In group living species, social interactions often involve two, three, or more individuals. In social interactions involving three or more individuals, each player should adjust its behavior while simultaneously considering multiple social factors (i.e., dominance ranks) associated with all the participants of the current interaction. Despite the interests in behavioral mechanisms underlying these multiplayer interactions in research regarding human and nonhuman animal behavior, previous studies have investigated the mechanisms in dyadic interactions; however, there has been no experimental study of triadic interactions to date. In this study, we examined the effects of relative dominance ranks on behavioral adjustment of inter-individual distances of large-billed crows (Corvus macrorhynchos), specifically in a triadic interaction paradigm. Three individuals out of five group-housed males, whose dominance ranks were determined prior to the experiment, were given the opportunity to freely interact in an outdoor aviary. Inter-individual distances of two individuals in the trio were measured. Distance distributions of the two individuals in the triadic interaction were compared to the predicted distance distribution, which was simulated by the distance observed in the dyadic interaction of the same individuals. The analysis revealed that when the trio involved the 1st dominant male, the distance between the remaining two males (i.e., middle- and low-rank males) was significantly shorter than the distance predicted by their dyadic interactions, but without any changes to their distances to the 1st dominant male. In contrast, no such change of distance was found in the two individuals when the trio did not include the 1st dominant male. An auto-regression model analysis to clarify the temporal relationship among movements of individuals during interactions suggested that the 1st dominant male's movements strongly influenced the remaining two males' movements with very weak effects of their movements on the 1st dominant male. These results suggest that, in triadic interactions, the 1st dominant male plays a significant role in causing subordinates to be within close proximity, which never occurred in their dyadic interactions.

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