A. This is one of the most common problems we face in avian practice- the bird without a mate that begins egg laying activity (the vast majority of which are cockatiels by the way). People are always very surprised when this occurs the first time because it is thought that a bird must be bred to lay eggs, which of course is untrue. Birds can be stimulated to lay eggs through several means. In the wild the photo period (day/night cycle) plays a role as increasing daylight and shorter nights herald spring/summer, an ideal time to raise young. However, in our home environment birds are essentially exposed to perpetual "long days" as when it darkens outside we turn on the inside lights so that the bird cannot follow a natural cycle. Thus they could undergo an egg laying cycle at any time of the year (remember the controlled indoor lighting that is used for egg laying chickens).

Other factors are also involved however. The bird must be "comfortable" in its environment, relatively free from stress so that a cycle can begin. Significant changes could upset the cycle.

Some form of stimulation appears to be involved as well. The bird is prompted into sexual activity by the photoperiod but other cues seem to get the cycle up and running. Birds are frequently seen stimulating themselves on toys/objects in the cage, even perches or on people in the household. Mirrors or favorite toys can be objects of desire for the bird. The bird can be stimulated by other birds vocalizing in the home or merely by gently petting the bird. So it can be seen that it may take very little to stimulate a bird into egg laying activity.

In the normal situation a bird will lay a clutch of eggs varying from 3-6 eggs then sit on the eggs until they hatch. On occasion you may have the solitary bird lay eggs in a clutch and then sit on them as if they were fertile. This is why many people recommend leaving the eggs in the cage with the bird. However, more frequently the bird lays one egg after another, usually ignoring the eggs that are laid. Should the eggs be left in or taken out? It depends upon the bird. If the bird "clutches" and sits on the eggs and does not lay anymore while she sits on them (until she tires of this) leave them in. Conversely, removing the eggs to eliminate the stimulus usually does not work by itself. Other means must be undertaken to stop this activity.

Is this egg laying dangerous for the bird? Absolutely! Excessive egg laying can lead to calcium depletion which could result in "egg binding", weakness, fragile bones with a great risk of fracture and even seizures. It is essential during egg laying in a bird, desired or otherwise, that increased vitamins and especially calcium are added to the diet. If the bird is not using the cuttlebone or mineral block, scrape it over the food or provide a supplement in the water. If the bird is already on a balanced diet the dangers are not as severe, however most birds are on unbalanced diets so the stress of egg laying can have grave consequences.

How do we stop the egg laying? There are varying degrees of aggressiveness and I prefer to start with the conservative measures first. If these fail then more involved steps are taken.

Initially I recommend changing the photoperiod to simulate "winter"-long nights and short days. That means placing the bird in complete darkness for 16 hours and daylight for 8 hours. This should be done for 2 weeks. A light cover is not enough-it must be dark. Usually placing the bird in a darkened room, away from the stimulations in the household, with a cover is adequate. In addition, removal of stimulating toys/objects (mirrors, etc.) are helpful. Do not physically stimulate the bird through petting. If you are stroking the bird and she is getting especially responsive then stop. If you have other birds they need to be removed from earshot of each other. Still another idea is to change the environment/surroundings of the bird by changing the cage around or placing it in a new location to "throw her off". These measures will work if followed strictly. You can institute them whenever the bird is showing sexual behavior, do not wait until the eggs have begun. These measures can also calm sexually aggressive birds-both females and males during their "cycle".

If these measures do not work then we need to get more aggressive with the use of hormonal therapy. The hormone used is testosterone (the male sex hormone) or a synthetic testosterone to negate the effects of the female hormone and cease the egg laying. It will also calm a sexually aggressive female, however, if the sex of the bird is unknown you do not want to provide more testosterone to a already testosterone driven male. The testosterone is usually given by injection or can be added to the water. We have had great success with a synthetic testosterone derivative Cheque Drops (used to keep female dogs from going into heat). It is safe and easily administered in the water or directly by mouth. The treatment period is usually for 30 days, and can be instituted when sexual behavior begins. the drug is well-tolerated by birds and we have given large doses safely.

Nonetheless, some birds do not respond to any of the aforementioned techniques so there is another drug that can be used, a progesterone compound, DepoProvera. This drug has received alot of press lately as it is used for long term birth control. It as it has an overall calming effect. It is effective in stopping egg laying activity and is used extensively in quelling sexual aggression in birds-both in males and females. The disadvantage is that there are side effects, increased water consumption, increased appetite, watery droppings, excess weight gain, lethargy and with repeated use the risk of diabetes. Thus this drug should be used cautiously. If used periodically it is safe but repeated, frequent use could lead to problems. Some practitioners are advocating the use of hormone impregnated implants.

If all other measures fail the last resort is a hysterectomy. It is difficult and dangerous to remove the ovary so removal of the uterus is usually effective. The advantage is that with surgery there will be no more eggs. However, as the ovary remains the bird will still display sexual behavior. Also there is always a risk when surgery is performed. So the decision to undergo surgery should be weighed heavily and done only in chronic problem egg laying.

Hopefully these tips will be what is needed to stop a problem that can eventually be very dangerous for the bird.