If we have our birds indoors we need to emulate nature. As the days become longer you will note behavioral changes in your birds. Using canaries as an example, the males will become aggressive, and the hens will start gathering paper, strings and feathers with which to feather their nests. It may become necessary to separate pairs until both are reading the same page of your bird book. If you want your birds to breed you need to begin to supplement their diet.
Vitamin E is reputed to assist in breeding.
In the spring when the grass grows, increase the amount of greens your birds receive. Somewhere I heard that hemp seed would increase breeding success. I grind it for the birds that can t crack it. Bugs, termites, grubs, worms, and whatever indigenous protein they can find crawling or flying. It is very important that we provide a good source of protein.