A multifunctional visual display in elegant trogons targets conspecifics and heterospecifics

Avian visual displays often target either conspecifics or heterospecifics, but few visual displays have been described where both conspecifics and heterospecifics are the intended receivers. In this study, combining observational and experimental approaches, we present evidence that a tail-raising display performed by the elegant trogon (Trogon elegans) is used in multiple contexts and is directed at conspecifics and heterospecifics. We observed tail-raising displays toward conspecifics in both intersexual and intrasexual contexts, as well as toward heterospecifics. Displays performed toward heterospecifics were directed at humans, monkeys, or birds of prey, all of which could have been perceived as potential predators. We experimentally tested the possible functions of tail-raising behavior in the presence of a predator by presenting elegant trogons with models of a natural predator and a nonthreatening control. Tail-raising displays were much more likely to occur when trogons were in the presence of a predator model (48% of trials) than a control model (6% of trials). The presence of conspecifics did not influence tail-raising propensity (conspecifics present: 44% of trials and conspecifics absent: 50% of trials). Our results suggest that tail raising in trogons is a multifunctional visual display that may function as an intersexual and intrasexual conspecific signal as well as a pursuit-deterrent signal directed at predators.