I've had four chickens fall into my pool. In two cases they were pullets that were trying to fly across it and had to 'ditch' in the pool and in one case one was chasing a grape I rolled over the kool deck and didn't stop in time and the third case, I don't know how the bird fell in, only saw it in the pool later. In all four cases, the birds...after initially panicking, simply paddled over to the side and hopped out and shook themselves off. They're quite bouyant and float like ducks and their feathers repel water pretty well. I imagine drownings happen when the bird can't get out of the pool and end up getting too tired but my experience has been that they can survive a fall into the pool quite well.
Edited by gallusdomesticus - 2/4/10 at 12:55pm