How to capture goldfinch in a cage. Place some food that the birds like to eat in the trapping area above the bird cage. Place the mechanical bird cage in a place where there are many birds, such as hanging it on a tree or in a bush.
You can also put a bird below and let it call out to attract friends. There is a small mechanism on the top of the cage. When an outside bird steps on it and falls into the cage, the small door at the top will automatically close.