What´s wrong with bows and arrows?
People still bow hunt for ground animals (obviously not a good option for ducks), but with a bow and arrow, you run a higher risk of wounding an animal without killing it, especially a large animal, like a deer. A rifle has more stopping power, and you can take a second shot in a few seconds, if you need to. The last thing you want to do is have a wounded animal run off into the woods and die slowly and painfully.
With birds, a shotgun sends out pellets that only travel a relatively short distance with a velocity that can kill, so shooting into the air is very safe. If you miss, the pellets falling from the sky will not hurt anyone or anything. The normal shotgun shell used for duck hunting is only lethal for about 40 yards, tops, after that, they just bounce off of whatever you hit.
CD