Hollywood Finches
01-23-2007 -
Extracted from the Vermont Institute of Natural Science (VINS) Blog
 In 1940 pet dealers on Long Island, New York, were illegally selling ?Hollywood finches? when they learned that the authorities were cracking down. So they opened the cages and let the evidence fly away. Four years later the first eastern house finch nest was discovered, and during the next 20 years small breeding colonies spread outward. The population grew exponentially, expanding its range across the eastern portion of the continent.
?Hollywood finches? are actually called house finches, a western songbird closely related to our native purple finch.
In 1968 Vermont's first documented house finch sighting occurred in Marlboro. The species debuted on a Vermont Christmas Bird Count in 1974 when two individuals were found on the Ferrisburg count. The first breeding record for the species occurred the following year in 1975 when a pair brought three young to a Bennington feeder.
In 1981, the Vermont Institute of Natural Science (VINS) started a fall migration bird banding station. Two years later, the first nine finches flew into the VINS mist nets. During 1991, 410 house finches were captured, far outnumbering any other species and accounting for 15 percent of the station's total captures that fall. By 1998 the population had crashed with only 13 birds captured. So what happened?
House finches began showing up at feeders in Washington D.C. with symptoms of an eye disease in 1994. It was soon determined to be Mycoplasmal conjunctivitis, a parasitic bacterium previously known to infect only poultry. The disease produces symptoms similar to what would be observed in humans - swelling of the mucous membrane around the eye and a crusty build-up of puss, which together impair vision.
By November of 1994 the outbreak had been reported in eleven states, from New Hampshire to North Carolina, and had spread from the house finch to the American goldfinch. This explosive radiation of conjunctivitis can be attributed, at least in part, to the gregarious nature of finches. Unlike chickadees and nuthatches for instance, finches will flock to feeders in groups and feed for relatively long stretches before flying away, increasing their chances of contracting or transmitting diseases.
It is important to clean your feeders about once every two weeks. For best results wash your feeder thoroughly in soapy water, then soak or rinse it in a solution of one part bleach to nine parts water, and dry thoroughly before refilling.
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