A Muscovy is not built like a cold-climate duck
A Muscovy in very cold weather needs a genuinely windproof house, deep dry bedding, and closer frost checks than a mallard-derived duck needs. Muscovies originated in warm parts of the Americas, and adults carry bare red caruncles around the bill and eyes instead of feathering. That exposed skin, along with their broad webbed feet, is where a Muscovy loses heat and picks up frost injury first. They are large, calm birds that perch like chickens when they can, and a Muscovy who can roost off frozen ground and out of the wind handles a cold night far better than one sleeping on ice-crusted soil.
Housing that respects a Muscovy's perching habit
Give a Muscovy a low, sturdy perch or a raised platform inside her shelter so she can sleep with her feet tucked under her body and off the cold floor. A heavy Muscovy drake is a substantial bird, so the perch must be broad and strong rather than a thin branch. Bed the floor deeply around it, because birds that come down at dawn land on whatever is below. Face the doorway away from the prevailing wind and keep a yard corner sheltered with bales or a windbreak panel; Muscovies wander and loaf outdoors by day even in winter, and a sunlit wind-free corner is where they will choose to sit.
Drinking water yes, bathing water no, in a hard freeze
A Muscovy does not need swimming water in winter and is safer without a pond edge rimmed in ice she can slip on or get trapped against. What she must have is a drinker deep enough to rinse her bill and face, refreshed when ice forms, because she uses that water to keep her eyes and nostrils clear while eating. Her caruncles suffer when she dips her face and then stands in bitter wind, so place the drinker in the most sheltered spot rather than the open yard. Break ice early, since a big Muscovy drinks a large volume at a sitting and will pace and call when the water is locked.
Extra feed for a big bird holding condition
Feed a Muscovy generously through a freeze, with her usual ration available all day and a filling grain scatter before roosting. A mature drake is one of the heaviest domestic ducks, and maintaining that body through cold nights takes real calories. Muscovies are also keen grazers who lose their usual forage entirely when ground is frozen or snow-covered, so the feed bill for the whole group rises even though appetites look similar. Add leafy greens or thawed vegetables as enrichment on indoor days, and keep grit out where she can reach it. Watch older drakes and birds low in the group order at feeding time, because quiet Muscovies get shouldered aside without much fuss.
Frost checks on faces and feet, and when to seek help
Examine a Muscovy's caruncles and feet each morning in severe weather, looking for blackened patches, swelling, or skin that has cracked and bled where she stood on ice. A bird limping on a frozen yard, refusing to come down from her perch, or off her feed should be moved to dry bedding in still air and a veterinarian consulted the same day. Frostbitten facial skin that stays dry often recovers slowly, but swelling, discharge, or a bird who stops eating points to something needing hands-on help. Keeping the whole household updated through KinsLe Family Sharing means whoever opens the Muscovy house sees the same shelter, water, and frost-check notes instead of guessing what was done.