Gardeners may actually be aiding the spread of the disease because infected bird baths and dirty feeders help the Trichomonas gallinae bacteria to spread. The bacteria cause’s birds’ throats to swell closed causing them to starve since they can no longer swallow.
Greenfinches in particular have been affected in Central England with almost a third of the population dying from bacterial infection this year. Chaffinches have also been affected losing a fifth of their population over the course of the year. A few isolated cases have also involved common garden birds such as sparrowhawks.
British Trust for Ornithology member, Mikle Toms, stated that the organization estimates that almost a half a million birds have been lost from the infection which has not occurred before.
Toms emphasized that proper cleanliness is the key to preventing the spread of the bacteria which includes washing out bird baths and feeders every other week if they are feeding birds. He added that if there are any signs of infection in the garden, such as the discovery of several dead birds in a short period of time gardeners should stop feeding birds.
It is believed that wood pigeons that have been forced into gardens in search of new food sources due to the changes in farming may be spreading the parasite.