Clay-colored Sparrow x Field Sparrow hybrid, Grand Isle, Lake Champlin (Vermont, USA), May and July 1998 - copyright Dave Hoag
(photo ID: 1801)
Vermont is outside of the normal range for Clay-colored Sparrow but Dave sound-recorded a singing bird on Grand Isle between 29th May and 5th June 1997. On 23rd July he recorded a second bird, but while this one shared the buzzy quality of Clay-colored Sparrow its song pattern, with added trill at the end, more closely resembled Field Sparrow. Its plumage was intermediate too, ruling out any possibility that it was a Field Sparrow that had learned Clay-colored song. Moreover Dave tells us that by August its face pattern remained different from Clay-colored Sparrow (not sharply defined as on worn adult Clay-colored), eliminating any chance that it was a Clay-colored Sparrow that had learned Field Sparrow song (also its bill was pink).
This bird returned in the summers of 1998 and 1999 when it was paired with a female Field Sparrow, and they raised 2-3 young successfully in 1999.
The Vermont Birds Records Committee concurred with Dave's identification and in 1999 the occurrence was published in Wilson Bulletin 111 (4): 581-584 along with sonograms of the bird's song.
Clay-colored Sparrow Spizella pallida
Field Sparrow Spizella pusilla
Very interesting. Is this the only recorded specimen of this hybrid type?
ReplyDeleteHi Gavin, other than the details given in the publication about this record in Wilson Bulletin (link in the last paragraph above) I don't know of any others. I shouldn't be surprised if there are more recent records that have so far escaped my attention though.
DeleteOk, thanks for replying. Checking the eBird species map, I have found only 3 other records of such a hybrid.
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