Ducks are aquatic birds whose natural behaviours are highly water-dependent. Farmed ducks denied access to open water cannot express fundamental natural behaviours, causing significant welfare compromise.
Ducks without water access experience chronic deprivation of behaviours that are central to their physical and psychological health. Eye and nasal cleaning requires submersion — without it, ocular disease and nares blockage are common. Preening with waterproofing gland oil requires water to be effective — dry-housed ducks develop poor feather condition that impairs thermoregulation. The welfare case for mandatory water access for farmed ducks is strong, based on both the species-specific importance of water behaviour and direct health outcome evidence.