Hi Marie,
You are correct that 12 eggs are far too many! And especially for a bird that is likely still too young to be breeding. She should be at last 2 years old before being paired with a male and given a nest box. And depending on how long ago she laid the 12 eggs, she may still need to be rested from egg laying. I would recommend separating them for a while, and not letting her have a box or nest or anything to encourage egg laying. In fact, I would make changes to try to discourage any more egg laying for at least 6 months. This will give her time to rest and by then hopefully she will be 2 years old. But if you think she is as young as a year, I would not put her back with a male for another year.
Captive bred birds will start to breed at much too young of an age – much younger than in the wild. It’s possible they mature more quickly in captivity, but the problem is they still have some physical and emotional developing to go through. A young hen is at a much higher risk of becoming egg bound and dying. And young birds are generally more interested in mating than settling down with eggs, so they develop bad breeding habits that often can’t be broken, like breaking or eating eggs, abandoning eggs or not caring for chicks. Laying eggs is a drain on a hen’s health – it takes a lot of protein and calcium, and also she needs to have fully developed muscles. Give her time to recover from laying eggs at a young age, and she is much more likely to be a good breeder for you. Also remember, once she does lay eggs, the nest box needs to be removed after each clutch, and the pair rested for 6 months before returning the box and letting them breed again. She should be limited to 2 clutches per year, which is one more than wild budgies have.
I would make these changes now, to discourage egg laying, and then each time they are due for their 6 month rest. Since captive birds do not receive the environmental changes that signal the end of breeding season, it is your responsibility to prevent them from breeding too often. It’s good that you rescued her because it sounds like the breeder did not practice responsible breeding practices.
You need to do all of these things to discourage egg laying. Keep in mind that to lay eggs, she needs longer daylight, warmer weather, abundant food, and a quiet, private environment. Your goal is to reverse these conditions.
Limit her light to 8-10 hours by covering the cage early each evening
Do not give her anything to use as a nest – no bird huts or tents, no box, bowl, etc. If she decides to sit in a food bowl, remove it and replace with smaller cups.
Do not give her anything to shred such as paper or cardboard.
Rearrange the toys in the cage frequently.
Move the cage to a different place in the room. Move the cage about once a week, or whenever she shows signs of nesting – settling on the cage floor for example.
If she is let out of the cage, do not let her get in any dark cozy places and don’t give her free roam.
If you handle her, limit any petting to her head and neck – do not pet her on the body.
If there is no metal floor grate, then do not use any bedding or paper in the cage tray – leave it bare and clean it daily.
Thank you for asking Lafeber,
Brenda