Not exactly on-topic, I guess, but it IS happening above my lawn and
garden...

I was working this morning in my office, which faces out to my back
yard, over my wooden deck, which has overhanging maple trees. I heard a
commotion in the tree, then a thump. When I went downstairs to look in
the deck, there was maybe three birds there, two of which flew away,
leaving a dazed-looking one just sitting there. After a while, I went
out, and the thing kinda staggered to the edge, then just sat there,
unable or unwilling to fly. Later, I found it had managed to get to the
railing, about 4 feet higher by jumping or flying. Now, about 4 hours
later, it has moved around on the railing a few times and was preening
itself a little, but it continues just sitting there... and now there
is another bird (similar in size and appearance) sitting right next to
it, both alive but quite still.

I don't know what kind of birds these are, maybe doves? They look a bit
like small pigeons, but with rounder, smooth heads and smaller pointy
beaks. Grayish-brown, not colorful. Maybe they're young-uns? I think I
saw a pair of these a couple of days ago chasing each other around
above my neighbor's house in what seemed to be a territorial dispute.

Can anyone guess what transpired? Did it maybe get attacked and knocked
out of the tree or sky onto my deck? Maybe it's young and can't fly yet
(it looks big enough to, though.) Could it be sick? Injured? Isn't it
unusual for another bird to cuddle up like this second one has? And
with all the alarmist stories in the news, should I be concerned about
West Nile Virus?