Instructions
Examine the egg for any cracks. If the egg is visibly damaged or if it has dropped from the nest or suffered any trauma at all, leave it on the ground. The embryo will not hatch in most cases. If an egg is incubated after suffering trauma, the bird is likely to suffer deformities. Only attempt to return an egg if it appears intact and has not suffered any trauma.
Look in nearby trees and shrubs for a robin's nest. Robins' nests are made with twigs and mud and lined with grass, and measure 6 inches wide and 4 to 6 inches high. The birds build their nests in plain sight, usually 5 to 15 feet above ground level. Female robins usually lay two to four eggs, so you may see additional eggs in the nest.
Place the egg back in the nest. As birds have a poor sense of smell, they will not be able to detect human scent and will not abandon a healthy egg touched by humans.