Waiting for the bus after work, I got to witness a mother trying to teach her fledgling how to fly in and out of this area-place. In was mastered without difficulty; Out was another matter. Mom spotted a crumb or somesuch, and swooped down out of the tree, baby following. She picked up the tidbit and fed her child, it was really quite cute. Then she fluttered back up out of the area into the tree.
Child didn't notice for a moment, looking hither and yon - Mom hadn't been in visual range when she took off. But her absence was soon noticed, and the youngster began to cheep. I've never learned how far house sparrows can see, but the fledgling's behavior was interesting - take a little hop, look around for Mom, not find her and give a cheep. After about three hops the behavior became a little more urgent, but not terribly so. Mom, meanwhile, is sitting up in the tree, calling back, but apparently "Up" is still a bit of a mystery to the young one.
So this goes on for a few moments - hop hop cheep (cheep-cheep), hop hop cheep (cheep-cheep) - to no avail, although the child has covered most of the area in its transit. At this point Mom flies down from the tree to perch on the lip of the area. Maybe if the kid looks up and sees her... Hop hop cheep. Mom gives up and flutters down, landing next to the chick. Cheep-cheep, cheep - words of welcome are exchanged, then Mom lifts off into the tree again. Oops, kidlet wasn't paying attention yet again. Down into the area flits Mom, right in front of baby's beak, then up off again. Ok, now the kid's got connection number one - Mom's not disappearing into thin air, she's flying off and back. Still not making connection number two - i.e. use your own wings and follow her. While this laborious thread has been spinning itself out in the fledgling brain, Mom has returned and taken off again.
About this time my bus rolls up, so I didn't witness the conclusion to our thrilling saga. I suppose I'll find out this afternoon, though even if gone, whether the chick finally flew out or simply hopped out around the open end will remain an unsolved mystery...