A Brief Primer On Hatching Ducks
Hatching ducks can be somewhat of a science. Even those used to working with and hatching chickens will find that hatching ducks requires a little more work and attention. Once you know what to do, things become fairly straightforward, and it probably doesn't need to be said that the reward at the end makes it all worth it.
Hatching ducks could be considered a four step process. First, the newly eggs are selected and examined to find candidates suitable for hatching. Eggs that are very dirty, have a crack in the shell, having an abnormal size or shape, or double yolked, can be discarder. The latter characteristic is determined by candling, holding a flashlight to the egg in a darkened room.
Storing - The second step in hatching ducks is one of storing the eggs before placing them in the incubator/setter. Sometimes the setter is not ready to be put in use, or more eggs need to be collected. The eggs don't have to go into the setter as soon as they are laid, but can be stored in a cool and protected place for a week or two if need be. If stored longer than that, their hatching percentage will start to go down sharply. When the eggs are ready to be placed in the setter they should first be brought to room temperature.
Setting - When placing the eggs in the setter, where they will remain for up to 25 days, place them small end down. The setter should have a feature that automatically turns the eggs several times a day. If it doesn't, turning the eggs will need to be done manually. This is critical during the first week. After a week, the eggs should be candled again, looking for signs of life, death, or infertility. If after 8 days, the egg is clear, it is probably an infertile egg, one that will never develop an embryo and hatch. If there is a red ring on the inside, a so-called blood ring, or red or black stains, the embryo has died. If the embryo is alive and well one should be able to see an emerging blood vessels and perhaps a small "body part". Candle the eggs a week or two later and watch for a well defined shape with evidence of a bill. Once the bill appears and there is also an air sac in the egg, it is ready to be placed in the hatcher.
A Sitter, Or Setter - Once the eggs are in the hatcher, it's sit and wait. When the eggs have been removed from the setter and placed in the hatcher, it's usually a wait of a day or two, seldom longer. If you want to avoid all the problems of hatching ducks, turning the eggs, candling them (still a good idea), maintaining temperature and humidity, and moving them from the setter to the hatcher, just hire a duck-sitter (setter), a female duck that will be more than happy to sit on the eggs and take care of the hatching process for you. Some species of duck may be better at this than others, but it’s a good thought. All you need is a sheltered, protected, and comfortable place for the duck to set.
As far as the actual hatching goes, most new hatchlings can generally work their way out of their shells without assistance, though in some cases it may take a day. If a little one is still struggling after 24 hours, a little gentle assistance is permissible. Baby ducklings need warmth, food, and water, each being a number one priority. They are natural born swimmers and will take to the water immediately if you let them. Don't let them, as it takes at least two weeks for their body oils to give them a water-resistant coating. If you place a hatching in the water, it will swim a bit, then get waterlogged and may drown. From freshly laid egg to swimming in the bathtub is quite an adventure, both for the duck and for its owner.