I've been driving for decades and pigeons ALWAYS get out of the way, but just now I was driving along and there were two pigeons in the middle of my lane. They both took off and one cleared me in plenty of time but the other one took off in time but then flew towards me for some reason. It glanced off my windscreen pillar and there was a huge puff of feathers, so I don't think it ended well for the pigeon.