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Peck is a useless move, as it is outclassed by other, stronger physical Flying-type moves. One example of such a move is Brave Bird, which has a Base Power of 120—compared to Peck's terrible 35 Base Power.
Brave Bird is a much more powerful option with 120 Base Power; however, it causes the user to take recoil damage.
Drill Peck is a more powerful option.