I don't know what it is about Welsh harlequin, but drakes seem to want to go after them and they get picked on more than others. I have had it in my flock and read about it in others. Eventually the drake and her should work things out. But until they do, it will not be fun for her at all. I am...
It seems like everyone always starts with a straight run and ends up with way more drakes than females 😆. That is great that he will be able to have a home with you.
I would introduce him the same way you introduce any new duck. Start with the look but not touch for a week or two. I would make sure he has an enclosure he can't jump out of. After your flock starts to lay down near the border, they can share the area but still have separation in the coop. Do...