I have two Dutch Doors at either end. I keep the bottoms closed and the tops open which keeps out ground critters. I bought some nylon screening and cut pieces to fit both top openings and attached either end to 1 x 2 pieces of wood. I screwed one end in above the doors, and I can roll up the screen on the other board and just place it on the ledge above the door when not in use, or I am going in and out. That keeps out bigger flying creatures. I have an automatic roof vent that opens enough on its own to let bees in and out.
