I won't worry to much about turkeys, they can and will roost in trees for up to a week or longer without feeding. When they do start feeding they can feed on just about anything and every thing and survive. The big worry for turkeys is they need gravel to digest there food. If they can't get to the gravel through the ice crust, they can eat all the food they want and still die with a full crop with no gravel to digest the food.