There are a number of reasons for which you may need to keep a goose egg warm without an incubator. You may have found that incubators are too expensive or too large for your purposes. If your incubator breaks in the middle of incubation, you will need a backup heat source. Or perhaps you have an egg hatching and want to move it to a more open space, yet still keep it warm. Fortunately it is fairly simple and inexpensive to create your own heat source for a goose egg.
Take the shoebox and set it on a stable, flat surface.
Put the 100 watt bulb in the desk lamp and set the lamp up so that it is pointing down toward the box.
Cover half of the box with cling film in order to help retain heat. Do this on the side that is farthest from the lamp.
Place a thermometer in the box on the side that is covered with cling film. Turn the lamp on and wait for 10 minutes.
Check the temperature. If it is above 37.5 degrees C, use the dimmer to turn the light down and wait 10 more minutes. Continue doing this until the temperature is at 37.5 degrees C.
Place a damp cloth in the box directly underneath the light. This will keep humidity in the air so that the egg will not dry out.
Place the egg in the box on the side that is covered with cling film. Continue to monitor temperatures to make sure they remain steady and re-wet the cloth when necessary.
Goose eggs take about 30 days to hatch. To increase hatching success, the eggs should be cooled each day until the 27th day. Do this by turning off the lamp and opening the cling film for 15 minutes. Spray the eggs with room temperature water. This is also a good time to turn the eggs, which should be turned 82.2 degrees C three to six times a day until the 27th day. On the 27th day, stop turning, cooling, and spraying the eggs. During the hatching period (days 27 to 30) you may want to decrease the temperature very slightly, but not to below 37.2 degrees C.
Alternative incubator methods will never be as stable as an actual incubator, so if you plan to hatch in high volumes and need stable results, this method is not recommended. Always keep lamps on a stable surface to avoid fire hazard.