What?s Wrong with That Bird?

Symptoms of common disease and tips on prevention

By Sarah Goodwin

Participants of the House Finch Disease Survey continue to contribute data from across the range of House Finches in North America. We would like to give big thanks to everyone who has volunteered time and effort for this important project.

Diseases can spread more readily in crowded situations. Keep feeders clean to help keep birds healthy.

Paula J. Sites/Project FeederWatch

Participants observe their feeders for the presence or absence of House Finches and the health of those present, and return their observations to the Cornell Laboratory of Ornithology to be analyzed. The level of commitment is chosen by participants, and the project is offered free of charge. The recent spread of House Finch Eye Disease, or mycoplasmal conjunctivitis, to the West Coast has encouraged new participants in the western United States and Canada to begin entering data. Now, to help better understand this disease in uncharted areas, we need even more participants from more geographic areas.

As the disease spreads and more participants become involved, questions about other diseases have become more frequent. The following are a few relatively common feeder-bird diseases that House Finch Disease Survey participants occasionally see. (Project FeederWatch keeps track of all diseased bird reports but the House Finch Disease Survey only monitors House Finch eye disease.)

House Finch eye disease: Affects mostly House Finches (other species to a much lesser degree). Symptoms are obvious; birds have crusty, weeping, irritated eyes and can show decreased activity. Often, only one eye is infected. Birds may also show symptoms of respiratory distress.

Avian pox: Affects a wide variety of bird species. Avian pox causes tumorlike growths on unfeathered areas on a bird?s body, including the feet, bill, and around the eyes. When the eyes are infected, this disease can be difficult to distinguish from conjunctivitis. If there is a lump or ?bulge? around the eye rather than uniform infection, the bird is probably suffering from avian pox. Avian pox is transmitted directly from infected individuals via a pox virus or indirectly by a mosquito.

Salmonellosis: Affects a wide variety of species. Birds suffering from salmonellosis may appear lethargic, with fluffed feathers. Birds may also shiver and shake. House Sparrows are common victims of this disease, although each season there are different small outbreaks in a variety of species. This bacterial disease is transmitted through fecally contaminated surfaces and food.

Aspergillosis: Affects a wide variety of species, usually birds with an already weak immune system. Aspergillosis is a fungal infection of the respiratory tract. Birds are frequently exposed to spores of this fungus, but weak birds that are exposed to numerous spores will become ill. Symptoms can be hard to discern, but birds often show respiratory distress (coughing, wheezing) and nasal discharge. Moldy seed is often the culprit for feeder birds.

Trichomoniasis: Affects mostly pigeons and doves, and the birds that eat them. Trichomoniasis is caused by a parasitic protozoan that causes an accumulation of tissue in the mouth and esophagus. Afflicted birds will often have ?puffy? necks and show difficulty swallowing. Pigeons and doves pass the parasite on to young during feeding.

Help prevent disease: To help minimize the risk of disease transmission at your feeders, keep feeders as clean as possible, using a 10-percent bleach solution once a week (let feeder dry completely before re-hanging). Also, if you have more than one feeding station, space them widely to discourage crowding. Rake up old seeds and droppings from below feeders because these are often contaminated. To keep the risk of aspergillosis at a minimum, store feed in dry, airtight containers and discard seed that appears to be moldy.

For further information on the above diseases, contact the National Wildlife Health Center www.nwhc.usgs.gov/. To help track the spread of House Finch eye disease, please contact the House Finch Disease Survey at housefinch@cornell. edu or sign up online at www.birds. cornell.edu/hofi.

Sarah Goodwin is project coordinator of the House Finch Disease Survey.

For permission to reprint all or part of this article, please contact Laura Erickson, editor, Cornell Lab of Ornithology, 159 Sapsucker Woods Rd., Ithaca, NY, 14850. Phone: (607) 254-1114. email: lle24@cornell.edu