i have two 7.5 week old mallards that are starting to glide around the yard and i want to clip their wings so they cant fly away. they will be shown at the local fair in oct. how often can i clip the wings, as for shows (as most of you know ;-) ) they should not me clipped and that can DQ them here...i keep bpuncing back and fourth on weather its 2 males, 2 females, or a pair lol. they free range during the day and are penned at night.