At night the hens are locked in, daytime they are roaming our backyard. We have multiple large black racers, raccoons, cats, rats, iguanas and at least one fox in the neighborhood. During daylight should I keep the aviary door close so the hens can go in for water and feed or should I keep it close to keep out the snakes, rats, etc ?
Have access to feed and water regardless how you do it. Not sure what your snake situation is like, I would check it regularly to see if snakes are there trying to munch on some eggs. Remove them and relocate them far enough so they do not return. Eventually your snake population will decrease significantly. I did that to the garter snake population in my yard. Soon there were none, or rarely would see one. In the beginning when we first got the home, we were over-run with them. There were a few neighbors that wanted some for their gardens. I gladly shared the catch with them. Rats will get into your aviary almost certain whether you close the gate or not. (they do not need large openings.) Raccoon will not be around during the day. If you do see one during daytime, be careful, as it may be sick. (possible rabies as well) . Fox will eat your chickens free ranging, and will not make himself comfortable in a vacant aviary. Have no IDEA on what to say about IGUANAS. It would help peeps give advice, especially climate related if you had your location included in your profile. Just a GENERAL LOCATION is fine WISHING YOU BEST,,,,,,,,,,,,,,,, and
Reminds me of a YouTube video where a possum snuck into the coop during the day, and wrecked havoc that night. Point is that one has to check the coop before lockup if you have your birds free ranging and the coop door open all day.