I am an aspiring goat owner. I want to buy 4 goats for maintaining a 4 acre, hillside fire line. My current plan to board the goats is to build a 30x30 fenced in area with a 10x12 lean to for the goats to sleep in. Will it be warm enough for the goats to not have a 4 sided structure? I live in southern CA. I am also concerned about predators, mostly mountain lions and coyotes. Is there a species of goat that can defend themselves against a mountain lion? I can't dedicate the time to sit on the hillside with a rifle to watch after the goats. I'd like to be able to leave them out during the day then board them at night. I don't have a dog right now and don't plan on getting one unless I have to.