I am new to keeping chickens and have a new coop. I do not have chickens yet, but I DO have 2 Raccoons that live on my property. My nest boxes are about 4 feet off the ground and open from the outside. They don't have a latch. DO I need to put one on? Can the Raccoons figure out how to open the nest boxes and get to the chickens? Any help/ advice on this would be appreciated. Thanks friends!