If a dove egg falls from the nest, there is still a chance it could survive if it is returned to the nest quickly. The adult birds may continue to incubate the egg, and if it hasn't been out of the nest for too long, it might still hatch successfully.

It's important to handle the egg as little as possible, as the oils from your hands can interfere with its ability to exchange gases through the shell. Try to place it back in the nest gently and without disturbing the other eggs or nestlings, if any.

After returning the egg, observe the nest from a distance to see if the adult birds return and resume caring for the eggs. If they do, the chances of survival for the egg are higher.

Remember that local wildlife authorities or bird rehabilitation centers may also be able to provide guidance based on your specific situation and the species of the bird.

Sources

Help!! Mourning dove nest fell, egg destroyed : r/Ornithology - RedditIs a bird egg still viable if it falls out of the nest but doesn't crack? - QuoraDove pushed her egg out of the nest! | BirdForumMourning Dove Moving its Eggs | BirdForum

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