Smew are rare winter visitors to UK freshwater habitats, with their welfare at wintering sites shaped by fish availability and disturbance.
Smew at UK wintering sites must find adequate fish prey in often unfamiliar waters. Disturbance from bird watchers, water sports, and dogs causes repeated energy-expensive flights at a time when foraging must be near-continuous in cold weather. Maintaining quiet zones at known smew wintering sites directly protects their winter welfare.