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What to do

House Finch Eye Disease

Avian Pox

Salmonellosis

Aspergillosis

Trichomoniasis

What do I do if I see a sick bird? Because feeders offer you an up-close view of birds, and because birds seek out "fast foods" when their health is compromised, you might someday see a sick bird at your feeder. Only veterinarians or federally licensed wildlife rehabilitators can legally treat wild birds. Therefore, if you find a diseased bird, it is best to report it to your state, provincial, or local wildlife agency. If a sick bird comes to your feeder, minimize the risk of infecting other birds by cleaning your feeder area thoroughly. If you see several diseased birds, take down all your feeders for at least a week to give the birds a chance to disperse. Remember that prevention is the key to avoiding the spread of disease. Regularly clean your feeders even when there are no signs of disease. Project participants can report sick birds observed during the FeederWatch season to Project FeederWatch using the Sick or Unusual Bird Form found in the Instruction Booklet or under Supplemental Forms inside of Data Entry. For more information on diseases affecting wild birds, contact the National Wildlife Health Center in the U.S. or the Canadian Cooperative Wildlife Health Centre in Canada. House Finch Eye Disease House Finch Eye Disease was first noticed in 1994 by a handful of FeederWatchers in the Washington D.C. area.
Birds infected with this disease (also called mycoplasmal conjunctivitis) appear to have red, swollen, runny, or crusty eyes; in extreme cases the eyes become swollen shut, and the bird becomes blind and unable to fend for itself. You might observe an infected bird sitting quietly in your yard, clumsily scratching an eye against its foot or a perch. While some infected birds recover, many die from starvation, exposure, or predation.
	Photo by Raymond Belhumeur, Saint-Hubert, Quebec
Conjunctivitis can have many causes, but the type most often seen in House Finches is caused by the bacterium Mycoplasma gallisepticum. This bacterium has long been known as a pathogen of domestic turkeys and chickens, but has been observed in House Finches only since 1994. The disease has affected several other species, including American Goldfinch, Evening Grosbeak, and Purple Finch, to a lesser degree. You can help us monitor the spread of this disease by contributing to the House Finch Disease Survey. For more information, visit the web site or call (800) 843–2473.   Avian Pox

Two forms of avian pox exist. In the more common form, wart-like growths appear on the featherless areas of the body such as around the eye, the base of the beak, and on the legs and feet.

	In the second form, plaques develop on the mucous membrane of the mouth, throat, trachea, and lungs, resulting in impaired breathing and difficulty in feeding. Secondary infections often develop, which ultimately lead to an infected bird’s death.
Photos by Chris Bumbar, Thousand Oaks, California
Avian pox can be caused by several strains of the Pox virus and has been reported in at least 60 species of birds, including turkeys, hawks, owls, and sparrows. The virus can be spread by direct contact with infected birds or contaminated surfaces (e.g., feeders), or by ingestion of contaminated food or water.

Salmonellosis

Salmonellosis is caused by a bacteria belonging to the genus Salmonella. It is a common cause of mortality in feeder birds, but the symptoms are not always obvious. Sick birds may appear thin, fluffed up, and may have swollen eyelids. They are often lethargic and easy to approach. Some infected birds may show no outward symptoms but are carriers of the disease and can spread the infection to other birds.

Salmonellosis is primarily transmitted by fecal contamination of food and water by sick birds, though it can also be transmitted by bird-to-bird contact. Occasionally, outbreaks of the disease cause significant mortality in certain species.

  Aspergillosis

Aspergillosus is a fungal disease that affects the respiratory system of birds. Healthy birds normally resist the disease, but birds with depressed immune systems are especially vulnerable. External symptoms include difficulty in breathing, emaciation, and increased thirst. Birds also can appear to have difficulty walking. When their eyes are infected, there may be a white opacity in one or both eyes, accompanied by a discharge.

Aspergillosis is a mold infection that is usually caused by Aspergillus fungi, commonly found in decaying vegetable matter. A bird becomes infected by the ingestion or inhalation of mold spores from contaminated foods. The infection causes lesions in the lungs and air sacs and has been reported in many species of birds. Occasionally, outbreaks of the disease cause significant mortality in certain species.

To reduce the risk of this disease, store seed in a dry place to discourage the growth of mold and fungus. Discard any seed that has become wet or moldy. Aspergillus fungi are most likely to grow on corn and peanuts. If you live in a warm, humid environment, you may want to avoid feeding these foods.

  Trichomoniasis

Trichomoniasis is a disease that most commonly affects pigeons, doves, and the raptors that feed on them. It is characterized by raised lesions in the mouth, esophagus, and crop. Infected birds may appear to have trouble closing their mouth. The disease is caused by the protozoan Trichomonas gallinae, which is often present in the mouth secretions of birds that appear to be healthy but are carriers of the disease, such as pigeons.

Infected birds can contaminate water containers (birdbaths) with their oral secretions, which can, in turn, expose many other birds to the disease. Mortality from this disease varies, but it can be quite high.