My ducks are 4 weeks old. We want to move them outside. They stay outside during the day. Weather is over 65 during the day and over 55 at night. They have been sleeping without heat lamp for the past two weeks indoors. Their outdoor enclosure is similar to a large kennel with a dog house inside. The kennel is safe from predators. The dog house is filled with straw but has no door. We tried to have them sleep outside but they refuse to sleep in the doghouse. Instead they lie on the wet mud in 55 degree temp. This concerned me so we brought them inside. Are ducks smart enough to move to a dry area to sleep if cold? Do I need put a door on the dog house and lock them in to keep them warm at night?