[texbirds] Re: Article on Solitary Vireo complex
- From: Martin Reid <upupa@xxxxxxxxxxx>
- To: texbirds@xxxxxxxxxxxxx
- Date: Thu, 2 May 2013 10:45:54 -0500
Dear All/Matt,
I'd like to thank Matt for providing an update on his feelings about this ID
conundrum. No doubt most of my claimed CAVIs are those which Matt would take
issue with! :-)
I would like to ask Matt to comment on a feature that for some reason I seem to
be fixated on: the border/divide between the pale throat and the dark
neck-sides. Looking at pics from the west coast I think I see some CAVIs (fall
males?) with a fairly clean division in this area, however the only pics of
BHVIs from further east that have a less-clean division also seem to have some
equivocal features (i.e. I see no bright, dark-headed, yellow-flanked birds
with a less than clean division). Then there are those birds which have pale
gray heads such that the lores is darker than the rest of the head - these
birds typically have the first few millimeters of the throat/neck divide
somewhat clean, with the rest being fuzzy.
Another feature that I thought was strong but may not be is the extent of (or
lack of) "dirtiness" on the throat, chest and breast area: I had the
impression that (especially in Fall when all birds are fairly fresh-plumaged)
BHVIs are immaculate on the underparts - ? This may be complicated by
intergrades from Alberta, which based on an over-simple assumption of migration
routes are likely to pass through the center/east of Texas...
I guess I have some questions - most of which are more for the purposes of
starting a discussion rather than in hope of there being a simple answer:
1) Can pure BHVI have a fuzzy neck/throat divide?
2) - if no, then what about the pale-headed birds with only a partially-clean
divide?
3) Is it likely that the majority of birds with fuzzy divides seen in the
eastern half of Texas are intergrades between BHVI and CAVI?
4) Assuming that intergrades are the best explanation for birds with some CAVI
features, can we draw a line on what qualifies for a good CAVI, accepting that
some birds that fall short of this line could well be "pure" CAVIs - ?
Regards,
Martin
---
Martin Reid
San Antonio
www.martinreid.com
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