Re: [SBB] Another oriole sighting

[Joseph Morlan <[[email protected]]>]

On Mon, 20 Mar 2006 15:29:17 -0800, Joseph Morlan <[[email protected]]> wrote:

>On Mon, 20 Mar 2006 14:29:29 -0800, "Michael Pollack"
><[[email protected]]> wrote:
>
>> Does anyone know if tail flicking is useful
>>in distinguishing between hooded and orchard orioles?
>
>Both species flick their tails.
>
>The status of Hooded/Orchard orioles in winter in California is very
>confused.  I have never seen an unequivocal wintering Hooded Oriole in the
>state and suspect that most (all?) orioles of this type wintering in
>California are probably Orchard.  
>
>Do you have photos?

Thanks to Michael Pollack and Mike Rogers, I have had a chance to review
Michael Pollack's excellent images of the bird online at:

http://www.untamedimages.com/backyard/gallery1-1.shtml

I also solicited an opinion on these photos from one of my colleagues.  We
both independently concluded that the bird is an Orchard Oriole, although
the bill appears a little thin at some angles.  Nevertheless, I think the
bill shape and relative size is a good match for the Orchard Orioles that
wintered in Golden Gate Park in 2003-2004.  See:

http://fog.ccsf.cc.ca.us/~jmorlan/orioles.htm

One helpful feature, besides overall size, is that Orchard Orioles have
relatively shorter tails than Hooded Orioles.  In Orchard, the wing chord
is longer than the tail and on Hooded the reverse is true.  Measuring the
wing chord and the tail on the Santa Clara photos indicates that the wing
is significantly longer than the tail on that bird. 

I think one of the best photos to measure is:

http://www.untamedimages.com/backyard/picpage1-8.shtml

..where the bend of the wing is clearly visible.  I believe these photos
eliminate Hooded Oriole.

Other subtle differences include the more rounded crown and plain face of
Orchard Oriole which impart a more gentle expression cf. Hooded Oriole.  I
think the head pattern on the Santa Clara bird further supports Orchard.

Voice is a helpful indicator.  Any oriole giving a loud whistled "wheet" is
a Hooded, but either species may give a low "chuck" note.  I think Hooded
Orioles are generally more vocal than Orchard.  A silent Hooded Oriole
observed and studied at length should raise a red flag.  

With regard to the status of each species, Michael Pollack referred me to
Bill Bousman's post to SBB back on 1/17/06:

>Concerning wintering Hooded Orioles, we have seen one or more in January
>about one year in four over the last 25 years.  Half of these have been
>males, so the ID is not an issue; the rest were females.
>
>There are no certain records of Orchard Oriole in Santa Clara County
>(although there have been some candidates).
>
>Bill Bousman
>Santa Clara County records compiler

Also Jeff Davis alerted me to winter records of Hooded Oriole in the
Central Valley including several in Fresno and Madera counties.
Nevertheless, Orchard Oriole has wintered in the Central Valley, e.g.
recently in San Joaquin County:

http://fog.ccsf.cc.ca.us/~jmorlan/oror31205.htm

Without attempting to evaluate any specific winter records of Hooded
Oriole, I am still inclined to the view that the Hooded Oriole is one of
the rarest of the orioles wintering in California as a whole, and I urge
extra caution in claiming wintering Hooded Orioles.   Neither Orchard nor
Hooded orioles should be considered more likely, and unknown orioles of
this type, including immature males) should not default to Hooded. 

Fortunately adult males of either species pose no identification issues.

-- 
Joseph Morlan, Pacifica, CA 94044  jmorlan (at) ccsf.edu 
Birding Classes start Feb 7 in SF  http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee  http://www.wfo-cbrc.org/cbrc/

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