Tuesday, February 23, 2016

American Goldfinch

On 18 February 2016, I banded this American Goldfinch. Because of its jet-black wing feathers, I knew it to be a male. The shoulders were not bright yellow, so I knew this was a second-year bird. Males in basic (winter) plumage tend to have variable amounts of black in their crowns. Males with more black in the crown tend to have brighter yellow bodies. McGraw and Middleton (2009) suggest that the possibility exists "of a non-breeding-season function to these ‘remnant’ colors.” Since my goldfinch is a second-year bird, its black crown feathers are probably not remnants from a previous summer, but recently molted—a sign of spring!

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