Avian Pox And Bird Feeders

Several years ago when I was new to bird photography I would often practice photographing the several species of birds that would come to my back yard feeder in order to improve my skills.  Later that summer I began to notice birds with deformities, especially on or near their bills, eyes, legs and feet.  At first I thought they were some kind of tumors but on the morning I took these shots I saw three birds (two House Finches and one Mourning Dove) that were affected so I became alarmed and took the photos to the vertebrate disease specialist at Division of Wildlife Resources here in Salt Lake City.  The diagnosis was avian pox.   Mourning Dove with avian pox growths on bill   Avian pox is a serious disease of many species of birds caused by several strains of avipoxvirus.  The most common form, cutaneous pox, causes wart-like growths around eyes, beak, legs or any unfeathered skin.  Those warts may interfere with feeding, sight, breathing or perching.  Affected birds often become emaciated due to the inability to feed.  Avian pox causes significant mortality in infected birds but they often recover as long as they’re able to feed.  There is no evidence that avipoxvirus affects humans.         Same bird, right side view   Birds become infected with the virus through direct physical contact with infected birds, ingestion of food or water contaminated by other infected birds or through contact with contaminated surfaces – especially at bird feeders and perches.  The virus enters through skin surfaces that have become abraded…

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