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View Full Version : Zonotrichia ID - Seaforth White-crowned Sparrow


AndyB
February 19th, 2008, 12:01 AM
Brett Richards posted the following in the Surfbirdsnews email group and I thought I would put it on here to see if any of our readers could comment. Better yet, does anybody have any photos of this bird?

The plumage Brett describes sounds odd and not sure I've seen or heard of a 1st winter bird with black crown stripes.

Hi All. Reading in the account of the Cley White-crowned Sparrow (Birding World 21:14-18) that “Peter Pyle has confirmed that, without exception, first winter birds retain their brown and rufous crowns until the pre-breeding moult in April” rekindled my concerns over the identification of the Seaforth bird on 2 October 1995.

Obviously not an adult White-crowned Sparrow, this bird nevertheless had what I described as ‘velvety-blackish’ coronal stripes, lores and eye-stripe. It also had a warm buff supercilium, rather than the expected grey. The illustration in ‘Sibley’ of 1st winter East Taiga does perhaps show a slight buff tint to the supercilium, but it is hardly warm buff, and the dark head markings are definitely brown rather than black or blackish. I also described the central crown stripe of the Seaforth bird as buff-orange, which again didn’t seem right at the time, but would perhaps accord with the ‘rufous’ quoted above.. I made the comment in my diary that it “appeared to be an advanced first winter ….” but “I can find no reference to the supercilium being warm buff rather than grey”. I still can’t, and my concerns over this bird have been increased by Peter Pyle’s comment above.

The identity of the Seaforth bird was never questioned as far as I am aware, and it was duly accepted by BBRC with no indication that there was anything unusual about it, so I put my concerns to one side; The bill colour & underparts pattern both fitted White-crowned, and ruled out White-throated, the only real confusion species, but can White-crowned Sparrow ever really look like this, or could it have been some sort of hybrid?

I did a bit of trawling around the web and found the following web links that might be useful:

John Dempsey's sketch of this bird (http://birdblog.merseyblogs.co.uk/archives/2008/01/happy_memories.html)

1st winter White-crowned with buffy supercilium (http://api.ning.com/files/9sJg2J2bk6YzN0g*ff94kg4*i1aiYL5K0QrjCZ1ypEY_/ImmWhitCrownSpar4.jpg)

White-crowned Sparrow showing just how rufous the central crown stripe can be. (http://picasaweb.google.com/jward199/SparrowsAndOtherSmallBirds/photo#4982846444520013842) and another one here (http://www.lauraerickson.com/bird/Species/Sparrows/White-crownedSparrow/Photos/HR2007/DSC07319.jpg). Here's another one (http://surfbirds.com/albums/showphoto.php?photo=4616&size=big&cat=) I took of a bird hitching a ride on a boat in the Pacific

Aberrant adult White-crowned or hybrid with Golden-crowned? (http://www.valdosta.edu/~bergstrm/zono.html)

Presumed White-crowned X Golden-crowned Sparrow (http://www.flickr.com/photos/nightjar/2181324245/)

Mark Szantyr's photos of presumed hybrid White-throated Sparrow x Dark-eyed Junco (scroll down page) (http://www.surfbirds.com/cgi-bin/gallery/search2.cgi?species=Dark-eyed%20Junco)

Marcus
February 19th, 2008, 07:20 PM
There are a couple of photos of the Seaforth bird by Steve Young in a "Photographic Handbook of the Rare Birds of Britain and Europe", they don't seem to be on his website unfortunately. Looking in the "Sparrows of the US and Canada" (Rising & Beadle) the bird does resemble the first winter leucophyrs depicted in this book, and the text states that "head pattern similar to adult except black and white replaced (respectively) by chestnut and buff, and ear coverts washed brown" They also say that hybrids have been reported with Harris's, White-throated, Golden-crowned and Song Sparrows.

In "Buntings and Sparrows - a Guide to the Buntings and North American Sparrows (Byers, Olson and Curson)" it states that the "head pattern as adult but black stripes replaced by dark brown and the white ones by greyish buff."

The photos of the bird aren't great quality and in one of them there appears to be a golden spot on the forecrown which may well be pollen, other than this it would appear to be in keeping with the aforementioned literature.

AndyB
February 21st, 2008, 07:07 AM
Thanks Marcus. Just looked at a photo. As you said, nothing anomalous seems to jump out. Dark brown head stripes - darker near forehead and buffy/rufous median crown stripe all fit well.