Supplementary feeding of urban wildlife by the public is widespread and affects individual animal welfare and population ecology in complex and sometimes contradictory ways.
Supplementary feeding of urban wildlife produces welfare outcomes that range from genuinely beneficial to actively harmful depending on what is fed, how it is managed and the species involved. High-quality appropriate food provided hygienically at well-managed stations can improve winter survival for birds and reduce stress during food-scarce periods. But inappropriate foods cause dietary disease, concentrated feeding stations spread pathogens, and habituation to humans increases conflict risk for animals that lose appropriate caution. The welfare analysis supports supplementary feeding when done correctly — species-appropriate food, clean feeders, appropriate quantities — and discourages indiscriminate feeding particularly of waterfowl with bread.