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However, the practice has changed substantially since becoming commercialised in the mid-20th century 8. This massive human intervention is likely to be having profound repercussions on the bird communities around us 5.Įarly feeding pioneers attracted a relatively simple bird community to gardens using kitchen scraps and home-made table feeders 5. In Britain, for example, homeowners are reportedly providing enough supplementary food to support approximately 196 million birds, far exceeding the combined, total population of many common garden species 7. In much of Europe and North America, the deliberate provision of food in domestic gardens and yards (garden bird feeding) has modified the winter resource base for birds extensively 5, helping to buffer against environmental drivers that operate through changes in natural food abundance 6. Winter food availability, in particular, plays a critical role in regulating bird populations in seasonal environments 1, with over-winter survival a key cause of population change for many terrestrial bird species 2– 4. Our findings illustrate the on-going, gross impact people can have on bird community structure across large spatial scales.įood availability may be the single most important factor determining the size and distribution of animal populations.

Urban areas of Britain are consequently nurturing growing populations of feeder-using bird species, while the populations of species that do not use feeders remain unchanged. We find that increases in bird diversity at feeders are associated with increasing community evenness, as species previously rarely observed in gardens have increasingly exploited the growing variety of foods on offer over time. Here we reveal a 40-year transformation of the bird communities using garden bird feeders in Britain, and provide evidence to suggest how this may have contributed to national-scale population changes. This extraordinary boost to food resources is almost certainly reshaping entire bird communities, yet the large-scale, long-term impacts on community ecology remain unknown. There is a multi-billion dollar global industry dedicated to feeding wild birds in residential gardens.