Hi I am new to mandarines ducks. Winter is coming and i wonder if i should coop them up in the barn. Right now they are in a pen with a pool..Soon i will not be able to fill the pool anymore. They have a door to go into the barn at night. But they havent done that. I covered there pen with plastic and tarps for the winter. Because i get lots of wind here. Also what should they be eating. I have be giving them chick grower and some laying mash. They are this year hatch. What treats can i give them?