Boost Your AF Performance - Outdoor Photographer | OutdoorPhotographer.com: "Birds flying directly toward the camera are easier to deal with than birds flying erratically across the frame. Keep the AF point on the bird’s head (very difficult, but gets easier with lots of practice). Don’t worry about the composition; you can crop as desired when you process the image. Concentrate on the moment and keeping the AF point on the bird’s head.
Nikon D300, AF-S NIKKOR 300mm ƒ/4D IF-ED, 1/4000 sec. at ƒ/4, ISO 800"