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Re: Gray-cheeked Thrush sighting from TGP has me puzzled (possible Bicknell's?) Even in New England, where Bicknell’s Thrush breeds, the locals separate them from Gray-cheeked almost entirely by voice.  Bicknell’s sing from about June 1-20 and at altitudes of around 3000 ft above sea level.   The Gray-cheeked has migrated north by then so the Bicknell’s is supposed to be the only one of the two present, but the song is the clincher.

Various Missourians have ventured to New England during the critical period, mostly to New Hampshire, to see them.


John Solodar
University City
St. Louis County, MO

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On 9/29/12 10:54 PM, "Douglas, Ryan" <[log in to unmask]> wrote:

Short answer…No, this bird is probably not a Bicknell's Thrush.

They're pretty much identical to Gray-cheeked and not really prone to wandering away from the East Coast, as seen in this eBird range map: http://ebird.org/ebird/map/bicthr?neg=true&env.minX=&env.minY=&env.maxX=&env.maxY=&zh=false&gp=false&mr=1-12&bmo=1&emo=12&yr=1900-2012&byr=1900&eyr=2012 <http://ebird.org/ebird/map/bicthr?neg=true&amp;env.minX=&amp;env.minY=&amp;env.maxX=&amp;env.maxY=&amp;zh=false&amp;gp=false&amp;mr=1-12&amp;bmo=1&amp;emo=12&amp;yr=1900-2012&amp;byr=1900&amp;eyr=2012>

From Cornell's Birds of North America Online:

"Gray-cheeked and Bicknell’s thrushes very similar in appearance and difficult to identify, especially in the field. Slight average differences in color of plumage and bare parts exist, but these less reliable for identification than differences in vocalizations and morphometrics (Ouellet 1993 <http://bna.birds.cornell.edu.proxy.mul.missouri.edu/bna/species/591/articles/species/591/biblio/bib058> , Knox 1996 <http://bna.birds.cornell.edu.proxy.mul.missouri.edu/bna/species/591/articles/species/591/biblio/bib047> ). Body coloration of both species varies across respective breeding ranges, obscuring differences in all but extreme variants."
 
Cheers,

Ryan

Ryan Douglas
Postdoctoral Fellow
310 Tucker Hall
University of Missouri
Columbia, MO 65211

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The Audubon Society of Missouri's Wild Bird Discussion Forum
Archives / Subscription options / ASM Website / Email the list owners

ABA Birding Code of Ethics

ASM Spring Meeting: May 3-5, 2013 in St. Joseph, MO. Details and Online Registration