I had a hawk come into my yard in the fall last year and go after my Delaware that is larger than my BO. The only thing that stopped the bird was me being on top of things.
Mine is currently chain link and I will be doubling up with chicken wire so yes I am willing to use the dreaded chicken wire. I live in town and my main predator is hawk.
They can and will come in even if you are right next to the dang chicken.
All you can do is do your best.