Just to clarify...I don't net my whole property, as that is not feasible...but I have found that strategic netting and strategic placement of streamers has been a very effective deterrent for hawks and birds in general.If that works for you, great - it's just not a viable solution for most of us.
If the OP was able to net his property, we wouldn't be talking about hawk protection.
Good luck to the OP, I do hope you find the right solution for your flock situation.
LofMc