Monday, April 25, 2011

Gambel's White-crowned Sparrow

Gambel's White-crowned Sparrow
Yesterday evening, while birding the Boy Scouts Area on Sandy Hook, I found this 'Gambel's' White-crowned Sparrow, Zonotrichia leucophrys gambelii.  This subspecies breeds on the northern tier from Alaska to Hudson Bay, and winters south through central Mexico, generally rarer eastward (Chilton et al. 1995).

It differs from the here on the Atlantic coast more expected nominate subspecies in having white/gray lores (black in leucophrys), an orange bill (pink in leucophrys), and a dull brown and olive back (ruddy brown and gray in leucophrys).

Here's a (crappy) photo of the nominate subspecies, in which some of these differences can be appreciated. I took this photo in dense fog on the 13th of April, 2011, here on Sandy Hook.

nominate 'leucophrys' White-crowned Sparrow
Compare this to the gambelii subspecies I photographed on Sandy Hook yesterday:

Gambel's White-crowned Sparrow
Since the gambelii subspecies does winter in very small numbers on the East Coast, it's impossible to infer where this bird spent the winter. It could be a western stray, but it could just as well have wintered among nominate conspecifics here in the East.

A detailed study of White-crowned Sparrow subspecies identification, highlighting the complexity of the issue, can be found on David Sibley's blog.

Cited literature:
Chilton, G., M. C. Baker, C. D. Barrentine and M. A. Cunningham. 1995. White-crowned Sparrow (Zonotrichia leucophrys), The Birds of North America Online (A. Poole, Ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online:
Sibley, D. (2010) White-crowned Sparrow Zonotrichia leucophrys. Blog entry on separation of White-crowned Sparrow subspecies,

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