If you are photographing birds in the wild, I think there are few opportunities to prefocus on the area where you expect to photograph the bird - there is waiting for the bird to takeoff, waiting for the bird to emerge from a nest hole, etc. But, there are some bird behaviors that you can try to leverage.
Spontaneous - you are not prepared but an opportunity turns up. One of my spontaneous catches is shown here. I was photographing stationary ducks, explaining the low shutter speed, when this small flock (not sure what they are - some type of field sparrow, I think) headed for me, then veered slightly.
Birds over water - nighthawks, swallows and other birds swoop to drink or pick up water. Sometimes they are predictable enough to provide a window. This is one situation where you *
might* be able to prefocus your lens to the neighborhood for faster acquisition.
Swallows riding the wind - swallows are very difficult to track, but sometimes conditions are right for them to turn into the wind and ride, almost in place, for awhile. At times you can also position yourself so that the swallows are heading toward you, returning to their nest, returning to a cliff resting place, etc.
Dragonflies - I like to practice on dragonflies in flight. They tend to hover over an area at times and may congregate along pond/lake shorelines presenting a rich practice environment.
Birds coming at you - as for the swallows mentioned above, if you place yourself so the birds are headed for you, that’s an advantage, at least for tracking and taking an in-focus shots. When the birds are coming right at you though, this often results in a not great aspect angle on the birds. It seems to me, many of the smaller birds like the ones in my example, pump and glide - so when they’re gliding with wings tucked back, that results in a boring shot. I’ve taken shots of grackles coming at me - they take the same route every day - but they turn out to be very boring photos.
-Nikon D850 and 200-500
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