Supplementary feeding of wild birds is widespread and beneficial for individual birds, but raises ecological questions about disease transmission and wildlife dependency that require careful management.
Supplementary bird feeding provides genuine welfare benefits to individual birds: in cold winters, supplementary food can be the difference between survival and death from hypothermia and starvation. Research shows that garden feeding improves survival rates and breeding success in blue tits and other garden birds. However, feeders that are not cleaned regularly become disease transmission points — the trichomonosis epidemic that has killed thousands of greenfinches spread via contaminated feeders. The welfare benefits of supplementary feeding are maximised by using the right food, keeping feeders clean, and monitoring for disease indicators.