[GarterGuy]

My very first garter that I had ( a T.s.parietalis about 3ft long) would not only eat fledgling sparrows (they would fall out of nest during storms where I lived), but also would eat strips of boneless chicken breast. Now this was a LONG time ago (I was 10 yrs. old!), and now I don't think I'd ever feed a wild bird to any of my snakes for fear of parasites and who knows what else. As far as the praticallity of it, mice are a lot cheaper and a lot easier to get a hold of. If you find some one who raises finches or quail or another small bird and you want to give them a "treat" it should be fine, but I don't think it'll really work as a practical food source.
Roy