I have a ~3.5 year old leghorn who decided to quit roosting with the other chickens in the hen house about a month ago. She hangs out with them during the day, but then disappears close to sundown. At first, she would roost on the fence, and I would catch her after sunset and put her in the hen house. She now roosts about 15 feet up in a tree, where I cannot catch her. With winter coming and below freezing temperatures at night time, I am concerned for her, not to mention the large owls we have in the area. Any suggestions?