What's wrong with the gray bird without breeding?

There are many factors that cause gray birds to not reproduce. It may be that they are not mature or they lack nutrition itself.This bird is generally built in the shrub or small trees, and it can be reproduced after the nest is built.Every year, 4 nests can be reproduced. There are 4-7 eggs per nest. Usually it will only be incubated for 16-18 days to get out of the shell. It will open your eyes for 10 days.Generally, 45 days will leave the mother bird.