Normal Laying Behavior:
Many bird owners are surprised to learn that a single female bird can lay eggs. They will not be fertile, of course. The eggs may be laid in a food dish or on the cage floor, or even somewhere in the house if the bird is allowed to wander outside the cage. Usually it is not common for a bird to sit on the floor of the cage unless it is sick, but a bird preparing to lay an egg will often sit on the floor and may shred paper if present to make a softer nesting site. Even a friendly tame bird may get aggressive at this time since her hormones are telling her to defend her nest. You may notice the droppings getting larger as the cloaca stretches out. (The cloaca is the area inside the body that droppings and eggs must both pass through.) Occassionally, a drop or two of blood may be seen on the first egg. The bird should be getting up to eat and drink every few hours. You might be able to notice swelling in the abdomen for a few days before the first egg is laid. The bird may lay only one, or there could be many eggs in the clutch, with a new egg appearing every 24 hours in small birds like finches, 48 hours in medium sized birds, or 72 hours in larger parrots.
Even a friendly tame bird may get aggressive at this time since her
hormones are telling her to defend her nest. You may see your bird
assuming a mating posture, which in females usually means she will
lean forward with her tail up in the air. She may rub her vent (the
opening of the cloaca) against a toy or the side of the cage, and may
make little squeaking noises. Birds that are allowed out of the cage
may start exploring underneath or behind furniture or inside boxes
and drawers to look for a safe, dark place to hide the eggs they want
Signs Of Egg Binding:
If the bird is having trouble passing an egg, she will often continue to sit on the cage floor and refuse to eat or drink. She may sit with her eyes closed and feathers puffed out from her body. She may not respond to anyone opening the cage or coming near her. This is an emergency situation. It is a good idea to become familiar with your bird's normal anatomy by feeling the abdomen when no egg is present, so that if you suspect an egg, you can gently feel her to see if there is an egg. Your veterinarian can assist you in examining your bird to help you know what to look for. Many people have been surprised by their 25 year old bird that suddenly laid its first egg when they thought it was a male for all those years. So keep in mind that even your "male" bird could get egg bound if the sex was not proven by surgical sexing or a DNA blood test.
What To Do At Home:
Heat and humidity can help some birds pass their eggs. Put the cage in the bathroom and turn on the hot water in the shower to steam up the room like a sauna. If it is too hot, the bird may start panting with its mouth open. You can also try soaking the lower half of the bird's body in very warm water. The water should be comfortable for you to keep your hand in without hurting. Attempting to put any kind of oil on the vent may just get the feathers greasy without getting any lubricant inside where it is needed.
When To Call The Vet:
It is best to call your veterinarian at the first sign of trouble. You and the doctor can discuss whether you should first try the heat and humidity and soaking, or if the bird should be seen immediately. Several options are available to help get the egg out. The proper treatment for each individual bird will depend on the circumstances, but may include injections, using a needle and syringe to collapse the egg, extracting it thru the cloaca, or even surgery.
Preventing Egg Binding:
Many cases of egg binding could have been prevented by making sure the bird gets adequate calcium and vitamin D in the diet. Preventing obesity and allowing the bird plenty of time to exercise outside of the cage may also help keep her in better shape for egg laying.
Things that may help prevent egg laying:
First, do not provide any sort of nesting site. Use a wire grate in
the bottom of the cage, or remove all paper or bedding material and
just leave the plastic or metal tray. Remove any boxes, and prevent
her from accessing dark corners in the house. Second, disrupt her
environment by putting her into a different cage or by moving the
cage to different locations within the room or into different rooms
of the house. This may make her feel that it is not safe to start a
family when her life is so unsettled. Third, reduce the hours of
daylight she receives by covering the cage with a heavy, dark blanket
for 12 hours each night. The increasing length of daylight hours
stimulates many birds to lay eggs in the spring and summer. Fourth, leave the eggs with her if she is sitting on them so she won't feel the need to keep laying more and more. Some birds need to have the pile of eggs to sit on for two or three weeks to help fulfill their nesting urge. Finally, save all the eggs she lays that have not been cracked. They will not go bad if the shell is intact, but will dry out so they rattle. If she starts another clutch of eggs, you can place all of the old ones under her to make her think that she has too many and should stop laying.
What types of birds are most likely to lay eggs:
Small birds, such as finches, lovebirds, parakeets and cockatiels,
may begin laying at one year of age. Larger parrots may be 5 or 6
years old, but I have seen them start at age 25!