Shoebills will usually not eat ducks especially if the duck is already alive.
Shoebills mostly feed on fish from the water.
There was a video somewhere I believe on Youtube showing a Shoebill actually picking up a duck and moving it in a friendly way.
So that Shoebill seemed to want to protect the duck.
Shoebills can fly if and when they want too.
Shoebills have the ability to fly when needed or when they want to fly but the Shoebill does not fly that often.
Because the Shoebill is a pretty large stork they don't fly too far and don't fly too often.
The Shoebill only flies sometimes and only as far as they need too.
The Shoebill also swoops down and eats fish from the water.
The fish that the Shoebills eat look almost as historic as the shoebills do.
You should be very caution around shoebills as well because although they are not all that dangerous they can be when they feel threatened.