The zoo is a great place for a telephoto, but it sucks for a fixed prime; you really don't have the freedom to 'zoom with your feet' when there's loads of fences or you might get eaten by a tiger or whatever. This probably goes for sport as well (less chance of being eaten by a tiger).
Really need to remember to set to Continuous Autofocus when shooting birds birds. And change the focus point. And if the lighting is bad, stick to Aperture Priority; shutter 1000 to freeze the action doesn't matter if the entire scene is pitch black
-I'm still really not sure about this 14mm... I think I liked the 20mm more, but need to work with this autofocus more...