Sadly, ducks don't actually have teeth. Though, they are quite proficient at ripping and shredding pieces off of larger objects to eat, potatoes are hard and not suitable for such a vigorous activity. I prep the poatoes and sweet potatoes for my sweet food forest ducks in a large, covered dutch oven. By filling the entire "floor" of the giant pot, I can make enough potatoes for several days at a time. 

Of course, I could probably get more in there if I were to cut them up before putting them in the dutch oven but... that sounds like far too much work. 

Anyways, bake them until a fork can be pushed into them easily. This way the ducks will have very little trouble tearing off bits for them to eat. 

In the future, I hope to improve this process by being able to harvest potatoes in the food forest and cooking them on a fire pit right outside and then returning them to the ducks for dinner time. So if you needed an excuse to build a fire pit, that effort will reduce the amount of times you'll have to come and go hauling potatoes in and out of the house to keep your garden birds fed. 

I'll also note that ducks love eating the shoots and vines on sweet potato plants, if you needed another reason to grow a hundred more sweet potato patches. 

After watching my ducks swipe large chunks of potatoes and greedily run off with them to take to the pond, wet them down and shove them into their mouths, I discovered that potatoes do not float. Imagine the disappointment of the ducks as what they thought was going to be a delicious meal sank to the bottom of the pond to eventually be gnawed on by the fish. 

So now I mostly give the ducks potatoes when they are locked in for the night so they can't lose half of their meal to greed and the deep water of the duck pond. 

While it is safe to give your ducks or chickens raw sweet potatoes, to hand over these hefty tubers whole would be setting them up for the fight of their lives, seeing as how they are toothless and can only crush things in their beaks that they can get into their mouths. With that said, with a simple food processor or a knife, sweet potatoes can be chopped into small, swallow-sized pieces for your birds, who seem to be somewhat indifferent to the hard sweet potatoes and still find them delicious and recognize them as food. 

This method allows you to cut up a lot of food at once and easily freeze it for the future as the chopped pieces are easier to put away than the whole tubers.