There's alot of mixed opinions on how many you can take out of a covey and not sure what life expectancy of a bird is either.Out here in west Texas dad taught me to size up the covey and then leave 25 to 40% of covey for seed stock.Some years if theres lots of birds and good covey concentration then we would take more and they would spread back to where we thinned the herd.On our land in Oklahoma the fire ants have wrecked the bird population to where we see 5-6 birds we are happy but don't even hunt them anymore.