For anyone interested in the previous Maine records, both of which were photographed, here is a link to the Maine Bird Records Committee page on Lesser Goldfinch:
A photograph of the 2009 Parks Pond, Clifton bird is linked there as are Lysle Brinker's photos of the Georgetown bird in 1992-93.
Cheryl Ring's excellent series of the Abbot bird are here:
A couple of mine start here: https://flic.kr/p/w2URUc
Margaret Viens has a series of photos (one page before and after this link):
Doug Hitchcox has some great photos starting here: https://flic.kr/p/wWqRtJ
Lesser Goldfinches are migratory in the northern part of their range, and the black-backed morph, like Ellen's and the other two Maine records, predominate in the eastern part of the species' range and are the only form from Mexico south to northern South America. One concern is whether some of the out-range occurrences could be escaped or released cagebirds. Male Lesser Goldfinches are excellent singers, as witnessed with the Abbot bird, and those are held in captivity in Mexico. I cannot tell from the plumage of this or the other black-backed birds that have been found in Maine whether they come from populations in Mexico or Middle America because those look like black-backed birds in the Southwest. The black ear coverts on the Maine birds suggests at the very least that they are not from populations west of New Mexico (e.g. Arizona and the Pacific Coast), where males have black caps and greenish ear coverts. It is a possibility that someone brings their "pet" to Maine (migrant workers?) and lets it go or it escapes. That said, the number of records in the East suggest some vagrancy (long-distance dispersal) occurs in the species, and most that is the most likely scenario. These records are about evenly split between spring-summer (FL, AR, LA, NC, IA, ND, MO, Ontario, and ME) and fall-winter (LA, AR, MO, KY, NC, WI, PA, and ME). The exceptional drought in the Southwest could be one driver, but it has been noted that the species will move into areas with recent, inundating rains (e.g. following passage of hurricanes or tropical storms), taking advantage of the flush of new growth. (The species is usually found in habitats around water.) These are temporary footholds, the population usually disappearing a year later. Other species in the West, where rainfall can be episodic and unpredictable, are known to wander widely in the same way. One example is Cassin's Sparrow, which has been recorded in Maine once, has also nested in California!
Louis Bevier
Fairfield
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