Sunday, January 29, 2012

Willet Mystery

Today I have a Willet mystery for you. Willets have two isolated populations. Western Willets breed from the Canadian prairies south through the Dakotas and west to northern California. Eastern Willets breed along the northeastern coast of North America. According to Sibley, you can identify these races in the field. Eastern Willets have broader, stouter bills. Western birds have broader wing stripes. Western birds are paler overall and have whitish central breasts; eastern birds are more uniformly gray.

Looking at my photographs, I conclude that the upper Willet is western, while the lower one is eastern. There is no problem with the upper bird--note the narrow bill and broad wing stripe--clearly a Western Willet. Western Willets winter on both coasts of North America, and this one was photographed on Sanibel Island, Florida. Eastern Willets winter south of the United States. My second photo, however, is from La Jolla, California. This bird, despite the broader bill and narrower wing stripe, should NOT be an Eastern Willet. Either this bird is well out of range or is an example of the dangers of field identification of avian subspecies. (The bird behind the mystery Willet is a Whimbrel.)

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