I was sitting in Church today in between Sabbath School and Church, and there was music playing. It was that rather annoying piano-and-bird-recordings type of music; the kind that usually comes in cd sets that also include titles like "whale songs" or "crashing waves". I listened briefly to the piano, but found it rather unremarkable. I then started listening to the bird calls. Most of them were mating calls or territorial songs with a few group calls thrown in for good measure. In other words, it went something like this: Sex! sex sex sex Sex! sex sex sex. Hey you! get off of that branch! You bastard! that's my seed! Frank? Katherine? where has David gone? etc. ect.
The speaker came to the front and made a comment on the nice music. I stared at my thumbs and stifled a laugh. People always think of birds as innocent little darlings, but that's kind of like assuming that all short people are kind hearted and ignorant. Bad idea. Never, ever, ever, look down at a short person and speak to them as if they are kind hearted and ignorant. The same applies to birds. When feeding pigeons or chickadees, never let your guard down. Chickadee language at the feeder can usually be translated as follows: "Hey! look! seeds! Come on everyone! Ok, now stay over there. I said stay there! These are my seeds! You jerk! (this is where they start fighting, the nasty little birds)

Basic Chickadee translation:
Chickadee-dee-dee; a call that family groups use to keep together when traveling. Also a warning call, the more "dee"s, the more danger.
Two quick chirps; startled, angry, sometimes used when the bird feels its personal space has been violated
Three quick chirps; an alarm call that causes the family to scatter
One gentle chirp; feeding call, used to call the group to a feeder or food source
Musical song (there is only one "musical song"); mating call