The RSPB has advised gardeners to remove seed and nut feeders between May and October to reduce the spread of trichomonosis, a parasitic disease that has severely impacted greenfinch populations. The charity recommends switching to small amounts of mealworms, fat balls, or suet instead, as these do not attract large clusters of finches.
Greenfinch numbers have declined by 67% since the Big Garden Birdwatch began in 1979, with an estimated 6 million greenfinches and chaffinches lost to trichomonosis in recent years. The species is now on the red list of endangered British birds.
Trichomonosis spreads more easily in warmer months when birds gather at feeders. The parasite can survive longer in saliva and fluids on contaminated surfaces. The RSPB advises cleaning feeders weekly, moving them regularly, and changing water daily to reduce risk.
“Feeding birds is something millions of us love, but the science shows that birds such as greenfinches have been affected by disease at feeders,” said Beccy Speight, RSPB chief executive. “We’re not asking people to stop feeding, just to feed in a way that protects birds’ long-term health.”
The charity also recommends planting sunflowers, teasels, and ivy to provide natural food sources and encourage insects, which are vital for chicks. During winter, seed feeders can be used again, but flat surfaces like bird tables should be avoided due to higher disease risk.
