Does duck change gender

[PaulX]

View attachment 1658372

Looks more like a dot than a disc to me, so I'd say not fertilized.

 

[GertrudeRonald]

I am really confused about my duck, she was a female with female plumage who laid eggs without yolks, just a speck of grey in the middle. Then she stopped laying eggs and changed feathers to drake colours. I thought she was just imitating drakes, but this morning I saw her mating with one of the hens and when she fell off and ran off I was shocked to see a penis dangling down just like the other drakes. Please can tell someone tell me what is going on.