Photography

normally, if you're shooting birds (and most other wildlife with a telephoto lens) you want to shoot wide open anyway...even if the animal is not captive with cage material to shoot through, there are branches, and foliage and other distractions that you want to render out of focus.

i can't remember which camera you had, but next time you go out to photograph birds, set the aperture to wide open (the smallest number) and set the camera to single point auto focus area mode and place the focus point somewhere near the center of the frame.....then when you see a bird within shooting distance, place that focus point over the eye, acquire focus and shoot.

when you shoot wide open, you're getting very little depth of field (range in front of and behind the subject that will be in reasonable focus) so you want to be dead on with the focal plane, and that's why you want to use single point auto focus area mode (instead of letting the camera decide where to focus)....the newer mirrorless cameras have animal eye detection AF area mode....i haven't tried it yet on my camera.