Comparative displays among four species of tragopans and their derivation and function

Abstract

This paper provides the first description and comparison of courtship behaviours in males of four species of tragopans in captivity. Inter-specific comparisons of each of the five displays (frontal, lateral, wing whir, flight, and lappet dropping) were similar with one main difference; Temminck's and Satyr tragopans assumed an arched posture, in addition to the upright posture during the lateral display. All frontal and lateral displays were performed only in front of females and most likely have a sexual function. In contrast, wing whir, flight, and lappet dropping displays were also performed in front of other males. Therefore, these displays are most likely to be sexual and aggressive in function and may also be a form of comfort behaviour in the lappet display. The first female displays are described for this genus. Intra- and inter-specific lateral displays in females were only directed towards other females and probably function as a threat display. Because of the similarities of the five displays among the four species of tragopans studied, courtship displays do not appear to serve as behavioural isolating mechanisms in zones of sympatry. However, lappet dropping, flight, and frontal displays are unique to this genus and probably function to reduce intergeneric hybridization. Female choice is probably based on differences in plumage colouration, lappet pattern and colouration, and vocalizations rather than display characteristics, as the former characteristics have diverged considerably as a result of sexual selection.