[Tweeters] Comments on the Bow Gyrfalcon Sighting

Bud Anderson falconresearch at gmail.com
Tue Jan 7 12:47:27 PST 2014

Identifying large falcons in western WA can be surprisingly difficult.

The gorgeous photograph taken over the weekend by Vicki Kings husband is
actually an adult gray Gyrfalcon, as she had first hoped. Congratulations

This bird is a full adult as shown by the bright yellow feet and cere. Plus
there are no retained, faded brown juvenal feathers in the wing coverts as
would likely be seen in a second year bird. This Gyr is a minimum of three
years old.

The color of the back is gray, not brown, with silver feather edgings
typical of a Gyr. Prairies never get this gray. Although hard to make out,
the tail is much longer than a Prairie Falcon. Prairie tails nearly reach
the tip of the tail. Gyrs primary tips are diagnostic, appearing to be much
shorter (ending roughly half-way down the tail) because of the extremely
long, almost accipitrine tail.

Also adult gray Gyrs have white breasts with gray spotting in the bib, gray
steaking in the belly and gray barring on the flanks. You can see the
latter feature clearly in this photo.

Not sure how to describe it but the head is Gyrfalcon not Prairie. Prairies
usually have a narrow white area between the eye and the auricular or ear
patch. Too much "Gyr white" on this birds head too.

Anyway, really great sunshine photo. Breathtakingly beautiful. Hope to see
this bird soon.

Bud Anderson
Falcon Research Group
Box 248
Bow, WA 98232
(360) 757-1911
falconresearch at gmail.com
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