Households are being warned to look for the signs of a deadly disease spreading among songbirds in the UK.
Trichomonosis, also known as ‘canker’ or ‘frounce,’ is a disease caused by a parasite that affects a wide range of bird species, though it is most well-known for its impact on greenfinches.
This microscopic parasite infects tissues in the bird’s mouth, throat, and oesophagus, making it difficult for the bird to eat and breathe.
While greenfinches and chaffinches are particularly susceptible to this disease, other birds—including sparrows, pigeons, doves, yellowhammers, goldfinches, dunnocks, great tits, siskins, and bullfinches—have also been affected.
Evidence suggests the disease can spread through bird feeders, particularly flat ones.
It comes after the RSPB withdrew flat bird feeders from sale on its website due to growing concerns that they could be contributing to the spread of the illness.
Gardeners are now being advised to look out for signs of sick birds in their gardens, with symptoms including lethargy, puffed-up plumage, and difficulty maintaining balance.
According to the British Trust for Ornithology, swelling of the neck may occur, feathers around the beak may appear wet, and affected birds may drool saliva or excrete a greenish fluid or a cheese-like substance from the beak.
People have also been urged to avoid using flat bird feeders, as bacteria from decaying food and waste from seed husks can build up, increasing the risk of infection.
The deadly disease is widely recognised as the primary cause of the rapid decline in the British greenfinch population, first observed in the late summer of 2006. This decline led to the species being added to the UK Red List in 2021.
However, it has been a known disease of cage birds for some time.
“Trichomonosis is caused by a parasite called Trichomonas gallinae. It is commonly transmitted on bird feeders and on bird tables, through consumption of food and drink contaminated by infected birds,” experts at the British Trust for Ornithology stated.
“Among garden birds, the disease is spread by infected parents feeding their young, and by consumption of contaminated drinking water or feed.”
How to safely feed birds
Follow the British Trust for Ornithology’s sensible hygiene precautions as a routine measure when feeding garden birds and handling bird feeders or tables.
- Regularly clean and disinfect feeders and feeding sites. Suitable disinfectants include a weak solution of domestic bleach (5% sodium hypochlorite) or specially designed commercial products. Always rinse feeders thoroughly and allow them to air-dry before reuse.
- Rotate feeder positions in the garden to prevent contamination from building up in any one area beneath them.
- Empty and air-dry water feeders or birdbaths daily to reduce the risk of disease spread.
You can report sick birds in your garden here.
