For several years now, we've had a little birdhouse hanging from the eaves on our back porch, and each spring chickadees raise a brood (or sometimes more than one) in it.
We never see the chicks inside, but they're loud. When a parent bird approaches with a beakful of grubs, the house is silent, but as soon as the larger bird pops in through the tiny entrance hole, the chorus of squee, squee, squee can actually disrupt our conversation a bit.
The behaviour of the parents as they approach is also fascinating. They'll fly up with food in mouth, yet land not on the house itself. Instead, they perch briefly less than a metre away, on the clothesline, or our hanging strands of Christmas lights. They peer around. They seem to be thinking, Safe? Safe?
Sometime's they'll make their distinctive calls: bee-boo or chicka-dee-dee-dee. But after a few seconds, they bolt straight into the birdhouse without pausing. The squee chorus mounts, and a few seconds later the parent flits off again without looking back—time to find more food.
The birds don't seem to mind when we're on the porch watching them. Even Lucy, our dog, pretty much ignores them. Given where the birdhouse hangs, it's nearly impossible for predators (especially rodents) to get at it, and the parents are bringing back juicy grubs every few minutes from gardens around the neighbourhood, so the chickadees have found themselves a good set of digs.