This female House Finch has what appears to be mycoplasmal conjunctivitis, a disease that this species is susceptible to (notice the swollen eye). It's important to clean your feeders, especially if you see a diseased bird such as this visiting them.
This disease has been documented in multiple other feeder species as well. It seems to hit the finches the worst, and I've seen both Purple Finch and American Goldfinch with this problem, but it is apparently not restricted to this family.
In poultry, MG transmission occurs by direct contact, air-borne droplets and dust, and through eggs, however not all of these methods have been documented in house finch infections. House finches transferred to empty cages which had held finches with conjunctivitis did not develop symptoms, although healthy finches kept in the same room as infected finches developed the disease. It is believed that the bacteria is spread between finches gathered at bird feeders, especially when large numbers congregate during cold weather
For Ohio area - Individuals who observe wild birds OTHER THAN HOUSE FINCHES at their feeder with symptoms of conjunctivitis can help by reporting the date, location (county), and species of bird with symptoms of MG to the Division of Wildlife, 2045 Morse Road, Bldg. G, Columbus, 43229. No effort should be made to capture the bird. If more than a few house finches show symptoms, you may wish to discontinue feeding for several weeks to reduce the opportunities for spreading the disease.
Last edited by Jeff Cashdollar; 02-10-2011 at 02:49 PM.
Thanks for the additional information Paul and Jeff. I'm somewhat relieved that the spread of the disease isn't caused by contact with my feeders after an infected bird has fed there. I was under the impression it was a "germs on the shopping cart handle/doorknob" type transfer but it's more of a handshake/kiss type I guess.....I'll still clean the feeders though.