I have had to split the pens when there is aggression that gets to be too much. Ours is related to mating season, so it's not all year but it is half the year. Sigh. I keep hoping things will resolve - but I would rather have the minor inconvenience of splitting them into two groups than the...
She may feel safer by the door. Sieben sits off by herself some of the time. That's why I named her Sieben (German for seven, a unique number).
Do take time and watch her, though. A duck may be feeling unwell and give only the slightest, or no, hints till it's serious.
And she may just be...