Lake Superior near Ashland, Bayfield County, Wisconsin
2 May 2012

From John Idzikowski:

"I do not have time for a descriptive analysis of each, but using loral angle and supercilium shape, bill shape and length to a lesser degree, back shape when foraging, barring of the tail where visible, the internal buff pattern of the coverts and scaps, and overall darkness of the terts, Lb is suggested for all 3.

Note also that the underparts seem to still be moulting which could suggest a more Sb hendersoni appearance -i.e. reddish buff with limited barring (but little spotting either) so we must be careful relying on the weight of other supporting chars. It is the internal buff markings of the scaps and coverts that contribute greatly to the overall appearance of alternate birds of both species- the more jagged tips of the buff markings make a Sb brighter and buffier and the Lb with more uniform buff markings darker overall as the black is presented more like black dots- just my take. And once wear begins alternate Lb's gets darker yet."