http://education.guardian.co.uk/higher/research/story/0,9865,1432991,00.html
Ducks behave pretty badly, it seems. It is not so much that up to one in 10 of mallard couples are homosexual ... but they regularly indulge in "attempted rape flights" when they pursue other ducks with a view to forcible mating. "Rape is a normal reproductive strategy in mallards," explains Mr Moeliker.
...
"Next to the obviously dead duck, another male mallard (in full adult plumage without any visible traces of moult) was present. He forcibly picked into the back, the base of the bill and mostly into the back of the head of the dead mallard for about two minutes, then mounted the corpse and started to copulate, with great force, almost continuously picking the side of the head."
Ducks behave pretty badly, it seems. It is not so much that up to one in 10 of mallard couples are homosexual ... but they regularly indulge in "attempted rape flights" when they pursue other ducks with a view to forcible mating. "Rape is a normal reproductive strategy in mallards," explains Mr Moeliker.
...
"Next to the obviously dead duck, another male mallard (in full adult plumage without any visible traces of moult) was present. He forcibly picked into the back, the base of the bill and mostly into the back of the head of the dead mallard for about two minutes, then mounted the corpse and started to copulate, with great force, almost continuously picking the side of the head."