In Pekin Duck and Mallard Duck the relationship between them and their presence since 2013 when the water was back at Coypu Pond are mentioned. This pair are the only two representatives left till today (April 2014) since approximately August 2016.
On March, 14th Nicolás witnessed this situation. "The pair was foraging around the area of the new viewpoint. All of a sudden, the male forces himself on the female. It does not control de the situation at all, insists a few times. The male seems to be having a ride on the female's back till she dives and gets rid of him."
So suddenly and with no previous displays this would correspond to a forced copulation. The evasive action of the reluctant female would announce no success. Mating in ducks is through penetration of a penis-like organ. The ducks are one of the few bird families which have a copulatory organ. It is corkscrew-shaped and is everted to copulate. This gives the male the advantage to take the female by surprise and xopulate without the female's consent or cooperation. But it is not so simple as that for the male. The female has evolved a very complex vaginal tract which is anti-corkscrew-shaped which makes it hard to penetrate.
This practice of forced copulation is rather common among mallard ducks, even with other Anas species. We have never witnessed an event of this kind with any of the other Anas of the reserve -the commonest residents are Yellow-billed and Silver Teals.
Between mallard ducks we have three records: pekin duck-pekin duck, pekin duck-female mallard duck and this last one mallard duck-female pekin duck. In the first case we found the ducks nesting. One egg laid but the egg disappeared. In the second one the two ducks mating but no nesting was observed afterwards and we will see what will become of this last case.
We have not witnessed cases of forced copulation in other duck species of the reserve. The matings detected were preceded by courtship displays.