Sexual dimorphism in adult Little Stints (Calidris minuta) revealed by DNA sexing and discriminant analysis

摘要

BackgroundThe sex of an individual organism plays such an important role in its life cycle that researchers must know a bird’s sex to interpret key aspects of its biology. The sexes of dimorphic species can be easily distinguished, but sexing monomorphic bird species often requires expensive and time-consuming molecular methods. The Little Stint (Calidris minuta) is a numerous species, monomorphic in plumage but showing a small degree of reversed sexual size dimorphism. Females are larger than males but the ranges of their measurements overlap, making Little Stints difficult to sex in the field. Our aim was to develop reliable sexing criteria for Little Stints in different stages of primary moult during their stay on the non-breeding grounds in South Africa using DNA-sexed individuals and discriminant function analysis.