Great bird photography comes from a successful collaboration of the right location, the right equipment, good technique, plenty of patience and an ounce of luck. If you approach a target-rich environment with the right lens and practice your technique enough — you will get lucky. (I paraphrase my husband’s motto: luck comes to the well prepared.)
The nesting arctic terns on Vigur Island in Iceland (a target rich environment) are very strong, fast and quick. They are busy catching small fish and delivering the fish to their chicks on the island. They also have an instinct to attack your head, so it helps to have an assistant guard your head with a stick.
Set your camera this way: fast shutter speed to freeze action, and all other settings to support that choice: higher ISO, wide open lens, spot meter, and maybe continuous shooting. Then, my technique was very quick action: pan/focus/shoot.