Ohmi Finch by Dr Ross Walker

Sexing Common Waxbills (Gender classification) — カエデチョウの性別判定

Common Waxbills are not visually dimorphic to any great extent, but there are some subtle phenotypical cues that can be used to help determine their gender

So let me state the obvious first, like almost all finches, the male Common Waxbill sings (a rather harmonic-laden song at that), while females lay eggs. Both of these cues are of little use when trying to determine the gender of individuals in a newly-purchased group. In terms of phenotyical differences between hens and cocks it can be said that cocks tend to have a greater extent of red on their breast than hens. I have found this to be true to some extent, but there are also many hens and cocks that have similar amounts of red on their breast, especially if they are still quite young specimens.

Perhaps the strongest phenotypical discriminator of Common Waxbill gender is the colour of their vent and undertail coverts. As can be seen in the image below of my eight specimens, even young cocks have deep black in this area, extending from the coverts to just past the vent area, and sometimes even extending up into the belly area. The brown areas on the belly of the cocks are also a darker shade than that of the hens.

Hens on the other hand tend to be much browner in the area of the vent and undertail coverts. Although you can also find black areas here, especially on the underside of the tail feathers, their vent areas tend to be heavily diluted with brown.

The images below show three adults (bottom right), age unknown because they were imported as wild-type specimens. The remaining five specimens were all only two months of age when these images were taken, so still quite young. However, those marked as cocks were practising their singing and already had deep-black coverts and vents.

Ohmi Finch by Dr Ross Walker