There are two main types of incubators in common use today: Still Air and Forced Air Incubators. Both incubate eggs in an enclosed environment such as a styrofoam cooler, carefully controlling heat and humidity. Forced Air incubators are similar to Still Air incubators except they use a fan to keep the temperature uniform. Still Air incubators use radiative heat to keep the eggs warm. Forced Air incubators use convective heating. Both use evaporated water to control humidity.
Mother ducks (and chickens) incubate through contact incubation. A mother duck's internal temperature is 106.5 degrees F. As she sits on the eggs and covers them with her feathers, the eggs stay warm. When she goes for a swim, she returns still wet and adds humidity to the nest.
We developed and tested an imitation Mother Duck incubator. We sewed tubing to a piece of cloth (similar to the cooling garments worn by astronauts) and strapped the cloth to the bottom of a stuffed animal. Then we used a pump to run water through a heater and through the tubing, keeping the water at 106.5 degrees. We put some stuffing in a box and put the eggs and then the stuffed animal on top. A few times a day we sprayed the eggs to simulate a wet Mother Duck returning from a swim.
Mother Duck Incubator -- 8 out of 12 eggs hatched
Still Air Incubator -- 7 out of 12 eggs hatched
Forced Air Incubator -- 3 out of 12 eggs hatched
For the Forced and Stil Air incubators, it was difficult to control the humidity, even with sponges and spraying. Several of the ducklings needed help getting out of their shells because with low humidity the shells were sticking.
The Mother Duck incubator had no humidity problems. We simply lifted the stuffed animal off the eggs, sprayed one or two times, and placed it back on the eggs. The ducklings hatched right underneath the stuffed animal and slowly wiggled their way out.
The Mother Duck incubator was also less messy and easier to use. The room temperature varied during the day from 70 to 40 degree F, but the incubator still kept them warm.
We believe this Imitation Mother Duck incubator would be great for schools and zoos. Ease of use, and a higher hatch rate, will be excellent for exotic and endangered species of birds. Children love it because it looks more like a real mother duck.