It's not uncommon, but not normal, for female birds to lay eggs without a male bird being present. If you find an egg in your parakeet's cage, you're probably wondering how it happened, what to do with it, and whether or not it will hatch.
If you have a female bird who lays eggs without a mate, it doesn't necessarily mean you're going to see a baby bird or that the egg will hatch. Unless the hen has been exposed to a male bird before the egg or eggs were laid, the egg will not be fertile. In this case, most bird owners remove the egg from the cage and throw it away. Most of the time, the hens go back to their normal routines.
There is no need for a male bird to be present for a female bird to produce an egg. Similarly to how women ovulate approximately every 28 days, female birds will also ovulate if environmental cues line up to promote reproductive behavior.
The Dangers of Egg Binding
Egg binding is a medical condition that affects female birds when they are unable to pass, or lay, an egg that has formed internally. This condition is common and can lead to infection and death for the bird if not addressed.
Depending on where the egg has become stuck within the bird's coelom, or abdominal cavity, it can sometimes be surgically addressed by a veterinarian. This professional will break the egg and remove it while the bird is under anesthesia. You should seek a certified avian veterinarian to assist with dislodging a stuck egg.
If the egg has broken while still inside the hen, any shell fragments or residue must be removed to prevent infection, and her oviduct—the avian equivalent to the fallopian tube—should be cleaned by a professional.
What to Do With Fertile Pet Eggs
If there is a chance that the egg your pet bird has laid is fertile and you want to raise the baby bird, you should candle the egg to see if it was indeed fertilized.
Candling is a process where a bright light is held behind an egg to illuminate its contents without cracking it open. A bird breeder can determine whether or not the egg is fertilized based on the color, shape, and opacity of the contents.
If you find the egg in your pet's cage was fertilized, you will need to either give it back to the mother for incubation or place it into an incubator if the hen will not sit on it. Keep in mind that raising a baby bird from hatching is quite difficult and comes with a lot of extra care and attention.