It could've been the wild birds too, idk. It also wouldn't make sense because he's been drinking duck water for awhile now, as have the rest of the flock, and he's the only one who got sick. And he's the second bird I've lost to those symptoms (terrible balance, yet normal personality/bright eyes, steady decline in health), but Canary was WAY before the ducks. :/
I've heard that duck is super greasy unless it's cooked right- but as long as mom cooks it I don't have any worries about that.
Could just be crappy quality birds too. I saw a BLR at Stockshow with similar coloring last year... I just about gagged (except she had a sweet little face

). BLR's are one of my pet peeves.