The general advice is to reduce the light exposure daily, although there have been no studies to know for sure if this helps. But it doesn’t harm the bird, so the recommendation is 8-10 hours of daylight, which usually means covering the cage in the early evening.
As Dr. Lamb explained in the webinars, cockatiels are so easily stimulated so just being where she can hear a male can result in unwanted hormonal behavior or egg laying. The biggest source of your Cockatiel’s frustration was being around a juvenile male. She wanted to breed and he wasn’t receptive as a juvenile. Your female took out her frustrations on herself, but often in this situation, the older bird that wants to breed will attack a non-receptive mate. Your bird plucked and ended up at the Vet, so I would take that as an early warning sign that she is going to be a problem bird with her hormonal issues. These are likely to continue if she is around the male. As far as preventative treatments, hormone therapy is usually a last resort when all environmental and diet changes have failed to stop the egg laying. It doesn’t work for all birds and also it can get very expensive. And there are risks with any drug therapy. If keeping the birds in different rooms doesn’t help, it would be easiest on her to rehome the male. I understand this would be a hard decision but consider birds can live for a very long time, so she could face years of health issues related to her hormones.
Thank you for asking Lafeber,