I have three birds that are always staying out at night. Squeakers, Avila and Greenie like to sit up on these paint cans that are ontop of a big shelf. Every night I have to go and get them down, and they never come down by themselves. Sometimes they see me, and go into a mad flight through the dark, bumping into the roof of our patio and sometimes hitting themselves so hard they fall to ground. Usually by then I can't get to them and they have to stay out at night. None have hurt themselves yet, but I'm pretty sure they will one day. What can I do help them come in by themselves?