Update: May 25, 2002: Here
are two recording clips from Alberta; they are copyrighted
by and courtesy of Jim and Barb Beck of the University
of Alberta:
Clip One is
representative of the BHVIs in Alberta.
Clip Two is representative
of the CAVIs in Alberta.
On the mornings of May 13 and 14, 2002, I heard and saw a "Solitary-type" vireo in my yard (located on southwest corner of Lake Worth, west of Fort Worth, Tarrant County, Texas). I did not attepmt photos, as I obtained very good views that confirmed it was either a very dull, poorly-marked Blue-headed Vireo (BHVI) or a bright-ish Cassin's Vireo (CAVI). It sang regularly, yet intermittently, for about an hour each morning, and I concentrated on obtaining audio recordings. I presume that it must be a male, given the persistent singing, thus I feel that the observed plumage would possibly be too dull for a male BHVI, yet well within the brighter end of the range for male CAVI (I wrote a full description).
The most ear-catching note in its repertoire was interspersed
about once every 8 - 15 notes, and is in this file: vireo1b.wav
(193Kb)
- to hear it in context, as the 4th note in a phrase of six (it
was typically preceded by a pause), listen to this file: vireo1a.wav
(2,532Kb)
The most frequent note-phrase was a two-note sequence typified
by this file: vireo1c.wav
(967Kb) - but with numerous minor variations in modulation; some
less burry, some more burry.
Another phrase that was used in unpredictable bursts (fairly long
sequences without it, yet some with it being used 2 or 3 times
in succession) is in this file: vireo1d.wav
(1,031Kb).
Some of the upslurred high notes were so rapidly-ascending that
they strongly recalled American Goldfinch's "jeiiII!"
note.
I would appreciate getting feedback
about these vocalisations (I have lots of audio, but the constraints
of my dial-up WWW connection limit me to brief cuts); especially:
- can BHVI be reasonably ruled out, based on these recordings?
- does it sound like CAVI?
- could PLVI be ruled out, based on the recordings (on plumage
it is definitely ruled out - this bird has obvious - yet dull -
greenish flanks and greensih edges to the remiges)?