Sorry, yes, it would keep them in as well. I would definitely use electric at different levels....obviously you don't want anything climbing your fence as the aviary netting won't keep anything out. You're right-predators have an odd way of multiplying once there is a potential food source out there. Also, the 4x2 spacing won't contain baby chicks-you would have to use hardware cloth along the bottom to accommodate babies if that's in your plan.
Given the large area, you may consider putting some taller supports in the actual yard itself to support the netting and give you room to walk around.