Most new bird guardians have no idea that their parrot is a sexual being. Parrots are not routinely spayed and neutered like dogs and cats. Therefore, all of their sexual hormones are present and they will go through stages of sexual maturity. This is important for you to be aware of and so that you can learn to manage your bird to avoid certain breeding behaviors. Most birds will enter into sexual maturity at a certain age, and it's different for all species. You might notice your bird maturbating, using toys or other objects to stimulte the area under their tail with. Or, your bird might regurgitate some food for you or for his toys. Your female bird might lay some eggs on the bottom of her cage.

Cockatiels are considered prolific breeders. They will breed and raise babies under nearly any condition. They will go through the motions of breeding even without a mate. Females will lay eggs, which can delplete their calcium and other resources. Male Cockatiels who are "turned on" can be quite aggressive.

Cockatoos and Amazons can also get aggressive during "breeding season."

If you notice two birds actually copulating, or if you find eggs in the cage of a female who has access to a male bird, you'll want to take some measures to insure these eggs don't hatch. It sounds cruel and mean, but your bird really won't mind, and you're saving yourself, your mother bird, and any potential chicks quite a bit of time, energy, and heartache. Having babies around might sound like fun, but it's a lot of work, and if your bird has never parented chicks before, she's going to find it quite stressful, and she may not be successful at it. Then you would have to decide if you could care for these additional birds, or if you'd have to give them away. Who knows what kinds of homes your chicks might go to. It's just best for you and for the birds to make sure the eggs don't hatch. You can do this by gently removing the eggs from the mother bird and shaking them up, or hard boiling them. Don't just take them and throw them away, as this will induce the female to lay more eggs to replace those she lost. Replace the shaken/hard boiled eggs and let her sit on them for as long as she wishes. She'll give up eventually and abandon them. After that, you can toss them.

Yes, in cages and in houses is sick both for the birds and their caretakers.  I think here in North America that the word "aviculture" has taken on a whole new weird meaning.  They think it means keeping birds caged in a human home, which sometimes is a cramped basement or apartment full of toxicity, so it's no wonder most of them die at an early age and there's so much fighting going on among people.  But after they are in aviaries, it is best to release them where they are free.  Tell that to some of these folks, and they go bananas on you.  They even have an Association of Aviculture, or something like that, which is run by a group of control freaks who never want birds to be free again because of a need for power and/or money.

To avoid inducing your bird, be sure to limit daylight hours (12 hours of light and 12 of dark are good), avoid letting him hang out in dark spaces like boxes and sleeping huts, and don't pet him or her anywhere but the head and neck area.