Courtship: The male goose engages in courtship behavior to attract a female. This may include bowing, honking, spreading its wings, and preening.
Mounting: Once the female is receptive to mating, the male goose mounts her from behind by standing on her back and grabbing her neck with its bill.
Cloacal alignment: The male and female geese align their cloacae, the openings used for excretion and reproduction. This alignment allows the male to transfer its semen into the female's reproductive tract.
Sperm transfer: The male goose rapidly vibrates one of its testes, causing semen to be transferred through its penis and into the female's cloaca. The transfer of sperm occurs in just a few seconds.
Disengagement: After the sperm has been transferred, the male goose disengages from the female, and both geese return to their normal postures.
It is important to note that geese mate in the water and may copulate multiple times during the breeding season to ensure successful fertilization. The female can store the sperm from the male for several days, enabling her to fertilize her eggs at a later time.