If you can let them freerange - do it. These birds are not like chickens. They are tougher than anything else you can buy and they freerange with nearly absolute success. They don't nest on the ground so that takes care of about 75% of danger. They roost high up in trees and are the most observant and unified flocks you're likely to see.
Who cares if their freerange pond freezes over? How do wild birds live? They don't need water heaters I can tell you that.
Who cares if their freerange pond freezes over? How do wild birds live? They don't need water heaters I can tell you that.