Sexing White-rumped Munias in Taiwan, using morphology, DNA and distance calls

Abstract

Methods of sexing the White-rumped Munia Lonchura striata phaethontoptila were investigated in eastern Taiwan. Twenty-six individuals were captured and their physical parameters were measured in the hand. Distance calls emitted when the birds were released were also recorded. The sex of each bird was confirmed using a DNA sexing method in the laboratory. Among the morphological traits measured, the tails and wings of males were significantly longer than those of females. An increasing stepwise discriminant analysis was performed to determine sex on the basis of morphological characters, however, only 84.0% of individuals were sexed correctly by such analysis. Distance calls of the White-rumped Munia were very similar to those of the Bengalese Finch, Lonchura striata var. domestica, the domesticated strain of the White-rumped Munia. Two distinct distance calls were recorded from birds on release, corresponding to the sexual difference confirmed by DNA testing. It is concluded, therefore, that the difference in distance calls is a useful trait that facilitates separation of the sexes in the field.