RSPB Warns Feeding Birds in Warm Months May Spread Disease
Providing food for birds in gardens is a common practice among millions in the UK, intended to attract and support local wildlife. However, the Royal Society for the Protection of Birds (RSPB), the country's largest bird charity, advises a pause in feeding between 1 May and 31 October. The organization highlights that bird feeders can become hotspots for disease transmission during the warmer months.
The disease of concern is trichomonosis, which has led to significant population declines in species such as greenfinches and chaffinches. Once commonly seen in UK gardens, the greenfinch population has fallen by two million individuals and is now listed on the red list of endangered birds.
Trichomonosis is caused by a parasite that infects the mouth, throat, and upper digestive tract of birds, impairing their ability to eat, drink, or breathe. Infected birds spread the parasite through their saliva and droppings, contaminating feeding sites. The parasite can also be transmitted directly to chicks when adult birds regurgitate food.
The RSPB's recent Big Garden Birdwatch data illustrates the decline, showing greenfinches dropping from seventh place in 1979, when the survey began, to eighteenth in 2025. It is estimated that over 16 million UK households regularly provide food for garden birds, with approximately one bird feeder available for every nine birds that use them.
The RSPB aims to slow disease spread by encouraging people to follow its updated guidance, though it recognizes that altering long-standing feeding habits may be challenging and unpopular.
The UK Pet Food industry estimates annual spending on bird food at around £380 million, equating to over 150,000 tonnes of food each year. This quantity could sustain three times the breeding populations of the ten most common garden bird species if they depended solely on this food year-round.
New Guidance: "Feed Seasonally, Feed Safely"
The RSPB's new advice emphasizes feeding birds seasonally and maintaining hygiene to reduce disease risk. It warns that a single infected bird can contaminate a busy feeder, turning it into a disease hotspot. Therefore, cleanliness is essential.
Small amounts of mealworms, fat balls, and suet can still be offered throughout the year but only in quantities sufficient for a day or two. Feeders should be cleaned thoroughly at least once a week, and if possible, relocated after cleaning to prevent contaminated debris from accumulating beneath them.
Water should be provided only if it can be refreshed daily, using fresh tap water. Bird baths also require weekly cleaning. Research indicates that disease transmission risk is higher on flat surfaces where contamination can build up.
Consequently, since the start of last year, the RSPB has ceased selling flat feeders and advises against their use, effectively bidding a "fond farewell" to traditional bird tables.
Public Reactions and Regional Considerations
Many individuals who regularly feed garden birds express that they will miss the close encounters. Helen Rowe, from the Isle of Dogs in London, contacted BBC Your Voice to inquire about safely continuing to feed birds. She describes a flock of sparrows that frequently visit the seeds and fat balls she leaves outside her home.
"It's really nice to see them from the window - they look very chipper out there," she said.
Despite enjoying the visits, she plans to stop feeding during the warmer months to avoid contributing to disease spread.
"I want to support the birds - I don't want to do anything that's going to spread disease," she added.
Some have questioned whether the guidance should be uniformly applied across the country, given the variability in natural food availability. Dick Woods, who operates a company producing easy-to-clean bird feeders and advocates for stronger disease control measures, commented:
"Every garden is different. In some places, food is so abundant that birds don't use feeders very much; in other areas there is little alternative."
The RSPB acknowledges regional differences but maintains that a single clear message is more effective.
"We are well aware that things won't change overnight and that behaviour change will take years, if not decades. We have therefore sought to keep our advice as simple as possible to make it easier for people to follow," said Martin Fowlie of the RSPB.
Industry Response and Scientific Basis
The pet food industry has expressed concerns about the new guidance, describing it as "a significant change to long-established advice" and warning that it may confuse the millions who regularly feed birds.
Michael Bellingham, chief executive of UK Pet Food, stated:
"The evidence informing these changes is still evolving, and much of the research underpinning this has not yet been published or widely scrutinised."
The RSPB counters that its guidance was developed in collaboration with scientists from the British Trust for Ornithology and the Institute of Zoology, based on a "thorough and robust" evidence review. The full report will be published online.
While recognizing the challenges this change poses for the bird food industry, the charity emphasizes the necessity of adapting practices.
"We cannot continue as usual," the RSPB stated.
Historical Context and Organizational Considerations
The risks associated with bird feeding have been known for over 15 years, prompting some critics to question why the RSPB did not update its advice sooner. Others have noted that the RSPB sells bird feeders and bird food, including products bearing its logo, through its shops and online store.
The RSPB explains that it has carefully balanced the increasing scientific evidence regarding disease transmission against the benefits feeding birds provides to both bird populations and people. Feeding garden birds can enhance wellbeing and foster a connection to nature.
The charity acknowledges the time taken to revise its guidance, citing the extensive process of gathering and analyzing evidence. It also plans to cease selling bird feeders and bird food during the warmer months.
