Just something that I think about sometimes... I work at our local Menards store as a night stocker. For those who don't have one, Menards is along the lines of Lowes or Home Depot (just better, of course! ) Anyhow, we have a seasonal garden center, not heated but the lights are on all night. It's also open to the outside in a few areas where freight comes and goes. There are a lot of sparrows in there, they found the bird food bags and eat all night. I walk in at any time overnight and a bunch of them fly up. The part I wonder about... do you think the lights in there make them try to lay eggs?