Yes it is true

The ducklings are usually waterproofed by the mother as she preens herself they get preened too and she waxs them with her own wax. So please don't try and swim them or they will get very soggy! They will learn from an earlier age to preen but their will be no oil till they are more mature. Try and make them something they can safely head bob in, so their eyes and nostrils can go underwater, a safe plastic container with clean stones in the bottom so it doesn't tip over and they can't get in but can wash their heads. This is really important with all waterfowl.

How are they now?