Cecil, with # 4's, if you took a shot at that bird flying, the shot will go a LOT farther than 100 yards. On the other hand, it you aimed just right at 100, your shot would not kill the bird, but still may be effective and keep him away.
You need to wait for the right opportunity where you can sneak up behind a pond enbankment. Being a weekend, I would get up at the crack of dawn, watch for him while posting on PB, then try to sneak up the slopes to get a shot. GOOD LUCK! They learn very fast don't they
