I have a REALLY bad problem with hawks in my area. I've already lost Brownie, my 7-week old duckling to a hawk, and after that I haven't let any of my ducklings truly free range. They're in 7'x12' pen with birdblock over the top, but hawks keep coming around looking for a way in (thankfully they can't get in). Do I still have to worry about hawks when my ducks are full grown? I have two 12 week old khakis, two 8 week old runners, and one 7 week old runner. My yard is an acre and completely fenced in, but only their pen has birdblock.