Using electric poultry netting sounds great for keeping out everything except for aerial predators which is what i will most have to contend with in PNW Washington. I could put some poultry netting or even just fishing line across the top but i imagine that would get tangled up as i try to move the paddock.
We had several structures that provided cover, but not for the entire pen. A couple yard carts, space under the portable shelter plus an awning on the side, an old patio umbrella used as a shade structure. Overhead anything did not work to move, although some people do it.
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An LGD may help with this. The one at my place watches for hawks, vultures, eagles, etc and will chase them away.
A sizeable paddock would be too difficult to cover. Maybe a hoop structure with chicken wire or shade cloth over it would work. For a large flock, it may work to create multiple covers, each covering a portion of the flock.
Our dog (not a LGD, but the kind of pet dog that lays around in the driveway all day and farts) needed to see a hawk get a duck before she caught on to the arial predator concept. Now, she is pretty diligent about watching the sky. So, do you have a lazy mutt?
Otherwise, a big rooster can be a big help. We don't lose egg birds to hawks anymore because they know when he (ruffles the rooster) signals to hide under the forest canopy. Can you put a tree in each paddock, or set your fence up around a tree?
The shade hoop Amos described sounds cheap and mobile, if not.
If you are in an open field, beware! We are adjacent to a dune, so warm updrafts mean torrents of predators spiral above on hot summer days. I sometimes wave them off, having heard that they have good memories, and hoping to instill a bit of "oh crap, human being!" along with the "mmmm, smells delicious" memory. They are much more afraid of the dog, FYI.
Good luck. There is nothing like death from above to strike fear in the heart of a poultry man.
1) Trees. Chickens totally know to fear Hawks et cetera and will dive for cover under a good tree. Several places I have lived/worked kept an Apple tree or two at the center of each chicken paddock. Hawks and the live generally wont dive straight through a tree to get at a chicken. That said I have seen them snatch more than one.
2) Crows. Crows will chase off hawks and eagles, especially when they are nesting in the area. Encourage crows, they totally will have your back.
To protect the chicks from hawks I learnead a trick from my grannies and it works, at least to the kinds of hawks we have hier in Brazil:
Castrate a rooster when it is still a teenager. When it becomes a adult rooster, it will "adopt" the chicks helping the hen to take care of them. The castrated roost will act as a watch, searching the sky for hawks and warning the hen by means of a sound when it sees anything suspicious. The chicks will hide then, I guess for instinct. As a plus, the hen will abandon the chicks a little earlier, going back to laying eggs and leaving the care of the chicks to the rooster.
I castrated my rooster at the vet but my grandmother did it by herself. There are a couple of videos on youtube teaching how to do it, too cruel for me.
I should say that where I live the hawks always predate the small birds, say less than 1 pound, never adult ones.
I'm still trying to solve this problem as well. I have a flock of about 30 birds and have the electronet fencing and a movable coop and trees in the paddock. I did have a rooster, but he would run away and hide when the predators came. I think he qualified as big since he became an 11 lb chicken dinner because he wasn't doing his job of protecting the flock. My flock is too small and my property is not fenced so a LGD isn't in the cards for me any time soon. To date I only loose about 5 birds a year so I think the problem is low enough with the conditions I have that I will just accept the losses.
You can see a little video of the owl that got caught in the fence in early spring.