Dippers are unique aquatic passerines whose welfare during cold weather depends on access to unfrozen, fast-flowing streams for underwater foraging.
Prolonged ice cover removes dipper food access, causing rapid starvation in a bird with no significant fat reserves. Cold-weather events are a natural welfare challenge, but water quality management that maintains diverse invertebrate communities ensures that when streams are accessible, food is plentiful. Clean, well-oxygenated streams represent the most important long-term welfare investment for dippers.