Depending on how many chicks, ducklings or goslings you need or want and the poultry breed of your choice, you may consider using an artificial egg incubator.
But before you go to the expense of buying or building an incubator ~ even a small and simple one ~ you should decide on how seriously you want to take the process of hatching. The problem is that some of the more highly-bred birds have lost the natural instinct to sit on eggs and the only way to rear them is through artificial means. But artificial does not necessarily mean artificial…
If you only want a few chicks from time to time, to replace your present layers, the best type of incubator to acquire is one that was developed by nature ~ namely a hen.
If you build a free range flock around the hens that go broody after a few years there should always be broodies available for further breeding.
And you can even use your broody hen to sit on other types of eggs. Naturally bred bantams, for example, can be easily enticed to sit on a few duck eggs and will happily sit out the extra few days between when chickens would have hatched and ducklings hatch.
However, if you wish for greater numbers or don’t want to rely on broody hens in your flock, you will need a small incubator.
The object of successful incubation is to match as closely as possible the conditions the egg would experience under a broody hen, or duck, or goose.
This includes constant temperature, movement of the eggs and, especially in the case of waterfowl, moisture.
Airflow
An incubator must not be airtight. Many beginners over-restrict airflow in their units. A well designed incubator will allow a constant flow of fresh air into, and stale air out of, the unit. Inexpensive incubators, especially the types that use light bulbs as heaters, usually don’t have enough heating capacity to allow for proper ventilation (if the vents are opened the unit cools too much). This results in the operator closing the vents in an effort to retain heat. The developing chicks then die due to lack of oxygen, because stale air is not being expelled quickly enough.
Temperature
A constant temperature over the whole area of the incubator chamber is vital. In a small table-top incubator you can approximate this constant temperature by changing the position of the eggs each time you turn them but in a bigger incubator you need a fan. More than one small fan is preferable, with each fan directed at a different angle, to ensure an even flow of air throughout the incubator, with no resulting cold spots.
A constant temperature throughout the incubation process is critical to success, and no less important than the correct temperature which should result in an internal egg temperature of 37 to 38°C. The problem with choosing the correct temperature comes with where one measures it and in what kind of incubator. In a fan incubator the air will be at a constant temperature throughout the unit if the fans are set correctly so where one positions one’s thermometer is not critical. In a fan unit one should aim for a temperature of 37,5°C
In a still air incubator the temperature will differ quite markedly from side to middle, front to back and according to the height in the unit. One should therefore position one’s thermometer in the middle of the unit, with the bulb at the height of the top of the eggs, ie 2-3cm from the floor of the tray, and aim to achieve a temperature of 38,6°C.
Humidity
Humidity should be maintained at about 55%, and increased to more than 65% at hatching time. An elaborate electronically controlled system is nice to have, but not necessary. In a small incubator nothing more elaborate is necessary than a tray of water at the bottom of the incubator. One can increase the humidity by increasing the evaporation area of the tray: simply add a lump of sponge or clean cloth that sticks up above the surface of the water. Getting the humidity right is not as critical as ensuring the correct temperature.
Buy a good thermometer or, better still, a hygrometer and set it up correctly. While a good thermometer is vital a hygrometer (also called a wet bulb thermometer) will enable one to monitor more accurately the humidity in the unit (not that one can control the humidity as accurately as one can the temperature).