Plumage Reflectance and Morphometric Variation in the Male and Female Chukar Partridges (Alectoris chukar, Galliformes)

Abstract

Introduction: The Chukar Partridge (Alectoris chukar, Galliformes) ranges from the Balkans to eastern Asia including Anatolia where is the western edge of its range. It is an economically important bird for Turkiye since being as a game animal, and thousands of partridges bred in captivity are released to nature by The Ministry of Agriculture and Forestry for hunting purposes every year. Chukar Partridge is a medium-sized partridge that both sexes are similarly ornamented. In other words, its sexes cannot be discriminated with the naked eye. Aim: We, therefore, examined the plumage reflectance and morphometric variation in the male and female Chukar Partridges whether the sexes of species differ from each other. Method: We measured 9 morphometric characteristics (head height, head width, bill length, bill width, bill height, wing, tail, and shape and length of throat and breast band) of 158 males and 45 females and 5-10 feather samples from 3 different body parts (breast, belly and tail) to measure the classic colourimetric variables (brightness, UV-range and chroma) were collected in this purpose from different parts of Anatolia and Trace. Both nonparametric and multivariant analyses were performed with R 4.0.2. Results: We found that male chukars larger and heavier than females. On the other hand, we found no significant differences in plumage reflectance. Discussion and Conclusion: Our results supported that male chukars larger than females. This means that chukar is a sexually dimorphic species in size. However, Further analyses such as the avian visual models are needed to better understand the colourimetric differences in sexes.