That is strange those ducks don't know where the food is. I haven't put the newest ducks outside yet, that's still several weeks away still until they can go into the grow out area.
I think they're figuring it out. Today, after being away for 4 hours, Sahara tossed some bread on the pond and they weren't even interested. Normally, they race over there and gobble it up. So I think they're finally figuring out where to go when they're hungry.