ducks and acorns

I aquired some runner ducklings in the early spring and they've been doing really well, however recently they've gone off their food and I think it's because they're eating the acorns from the oak tree over their pond. The ducks seem fine, but I'm worried acorns won't be good for them...or the family when we eat the eggs.  Should I be worrying or not ?     

Welcome to the forum.  Could you post some photos of your ducks, we all love photos.