Hi Virsayit,
Birds do not need a male in order to lay eggs, but of course the eggs will not be fertile. It’s the same as the eggs you buy at the grocery store – egg farms only have hens, no roosters.
Single cockatiels are notorious for laying eggs. It can become a chronic problem and is very bad for their health. Your bird will probably lay 4-6 eggs, with one day between each egg. You do not want to encourage egg laying or incubation. Do not give her anything she can use as a nest, and she does not need a heat light. This can put her in an endless egg laying cycle which can eventually kill her. Some females get stuck in this cycle and you have to take her to an Avian Vet for hormone shots or an implant.
There are changes you can make to discourage egg laying. Never give her a nest, box, bird tent or hut or anything she can sit in. Leave her eggs on the cage floor – if there is a metal floor grate, this is ideal because it does not make a comfortable place to sit on eggs. If there is not a grate, remove any cage bedding or paper and just leave the tray bare – you will just have to clean it daily. Do not give her anything she can shred like paper or cardboard, and no bedding on the cage tray unless the cage has the metal floor grate. If she lays eggs in a food dish, take the dish away, and replace it with smaller cups – the eggs can be placed on the cage floor. Limit her light to 8-10 hours by covering her cage early each evening. Rearrange the toys in her cage, and move her cage to another place in the room. You may have to move the cage every week to keep her from settling down and laying more eggs. When you handle her, only pet her head – if you pet her on the body this can trigger her hormones and egg laying. When she is out, do not let her get into dark cozy places. Keep the young male bird away from her. He is too young to breed, but his presence can make her lay more eggs. If you had planned to breed them, you have to wait until he is two years old. And neither bird will remain tame if you decide to breed them. It is very important that you make these changes. In the wild, cockatiels only lay eggs once a year, and then the seasons change and they stop until the next year. In captivity, they do not get the environmental signals, so they can get stuck in an egg laying cycle. It is hard on her health and as I mentioned, if you don’t make changes to stop her, or take her to the vet for hormone treatment, she will eventually die from laying too many eggs.
Thank you for asking Lafeber,
Brenda