[texbirds] Green backed Rufous Hummingbirds - setting the record straight

From: Kelly Bryan <kelly.b.bryan@xxxxxxxxx>
To: texbirds@xxxxxxxxxxxxx
Date: Mon, 26 Aug 2013 16:23:21 -0500

Dear Texbirders,
Michael Stewart's bird is a prime example of a Rufous Hummingbird with an
approximately 50% green back.  Thanks Michael for posting those pics.  For
the past four years I have been scoring the amount of green in the backs of
RUHUs here in west Texas.  Percent of green from the bottom of the nape to
the top of the rump.  Through 2012, I scored 176 adult male birds with the
following results:

0 green - 73
1-5% green - 60
6-10% green - 9
11-20% green - 10
21-30% green - 6
31-40% green - 10
41-50% green - 4
51%+ - 4

Most green backed RUHUs originate in the NW Oregon/SW Washington area.
 This is per Dr. Chris Butler, a professor at Oklahoma Central University.
 Dr. Butler grew up in Portland and now does research in Oklahoma on
hybridization in BCHUs and RTHUs.  Chris was recently here in the Davis
Mountains and we were discussing this very topic while banding with his
class at the Davis Mountains Preserve.  He said that early banding studies
in that northwest region were calling all of these birds ALHUs until
advancement in measurement data and feather structure discounted those
early IDs.  They were all RUHUs.

Given the above data that I have collected, it is likely that any of these
birds can show up at any location in Texas.  Mark Lockwood is right that
the opportunity to closely observe, and in my case examine ALHU in had,
provides tremendous insight into being able to ID them in the field.  ALHUs
are 20% smaller on average than RUHUs and have a different demeanor.  All
of my adult male ALHUs have had complete green backs with a clear line of
demarkation between the green lower back and pure bright rufous rump.  Hope
this helps with this discussion.  KBB

-- 
Kelly B Bryan
Fort Davis, Texas

To follow the progress of my hummingbird project go to:
http://westtexashummingbirds.com/
To support this project, other bird projects and our educational outreach
in west Texas go to:  http://www.westtexasavianresearch.org/


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[texbirds] Green backed Rufous Hummingbirds - setting the record straight

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