Until I could get bird netting over my 4,000 SF run, I ran reflective tape, criss-crossing , all over the run. Having already had an eagle attack, I found this worked. But, of course it was hard for me to get around the space too. But, eagles swoop down on their prey, and I have watched a small hawk just drop nearly straight down on a dove, so that may make a difference. Still, I think it is a deterrent. The reflective tape can be found in any farm store. I think it's also called deer tape. Folks put it along the top of a fence line to deter deer.
Hope this helps. We don't have large hawks in my immediate area because we have a pair of bald eagles, and they chase away any competition. But, I will tell you, the bald eagle attack was so devastating that I lost one of my favorite girls to shock a couple days later. She wasn't personally attacked, just traumatized. It was heart breaking. So, do whatever you can to keep them safe.
And when you get back, it might be time to start planning a sufficient secure run for them in the future. In addition to the netting, we have also done that now.
