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Multiple regression analyses were used to compare distributions of nine common waterfowl in Britain with six independent variables related to the ecology of inland waters. Large sites tended to hold more waterfowl than smaller ones and relationships with the crinkliness of the shore were probably due to the fact that many sites are primarily roosts and that large reservoirs have relatively simple perimeters. Chi-square analyses were used to test presence of different water-based recreation in relation to the observed number of birds as compared to the number predicted by regression models. Species most susceptible to disturbance from recreation were green-winged teal (Anas crecca), northern shoveler (A. clypeata), and common goldeneye (Bucephala clangula). Most tolerant were mute swan (Cygnus olor), tufted duck (Aythya fuligula), common pochard (Aythya ferina) and mallard (Anas platyrhynchos). The greatest deleterious impact on winter wildfowl numbers was associated with the presence of coarse fishing, sailing, and rowing. The presence of birdwatching was associated with higher-than-expected numbers of most species.