The most astonishing on-bike experience in an urban environment was riding on a waterfront MUP as a short-cut when a duck took flight about 100 yards to my left but headed in my direction. The thing is, the bird kept coming, and coming, and coming, until it flew, quacking its head off, about six inches above my helmet. Crazy!
Another wildlife encounter was on a randonnee with two other riders in a paceline around 2am. A possum ran across the road, bounced off the rear wheel of the leading bike, hit my front wheel, then dashed between me and the last rider before bounding up a timber fence. As riders, we were all extremely lucky not have ended up as an ugly mess on the road. The best part, is everyone, possum included, was unhurt.