20-B-2017 Gyrfalcon

STATUS
Accepted
DATE VOTING COMPLETED
1ST ROUND
7-0
DATE SIGHTING OCCURRED
DATE REPORT PREPARED
REPORTER
Tempe Regan and Jay Carlisle
OTHER OBSERVERS
Joni Clapsdale
LOCALITY OF OBSERVATION
20 Mile South Farm (restricted access), Ada County, Idaho
HABITAT WHERE THE BIRD WAS OBSERVED
grassy agricultural land, some fences, surrounded by sage steppe
SIGHTING DURATION, CONDITIONS, and EQUIPMENT USED
clear, light breeze
DID YOU TAKE NOTES?
No, not at all
DID YOU CONSULT A FIELD GUIDE OR OTHER REFERENCE WORK?
Yes, during the observation
WHICH GUIDE(S) OR REFERENCE(S): DID YOU CONSULT?
Sibley app and Ibird Pro app
DESCRIPTION OF THE BIRD(s)
Extremely large falcon, long wings, broad wing-base, deep strong wing beats. Wing tips not to tail when perched. Uniform gray/brown above, uniform streaking below. No dark armpits and much larger and stronger flapping than Prairie. Hunting mostly, perched for a short time. Probably a female based on immense size.
BEHAVIOR OF THE BIRD(s)
first seen flying/hunting then perched on a fence when photos were taken. Then flew to SE and out of sight in a draw.
HOW AND WHEN DID YOU POSITIVELY IDENTIFY THE BIRD, AND WHAT CLINCHED THE IDENTIFICATION FOR YOU?
When I first saw this bird, my instinct was “what is that huge falcon? It is too big to be a Prairie.” I asked Jay to take a look and he immediately was thinking something big, like Buteo sized (his immediate impression was a Ferruginous Hawk based on tapering wings until he saw it start flapping and realized it was a huge falcon). As we watched it in flight for a minute or more and from a distance of 700+ meters, although we never got spectacular looks at it, we were able to determine it was definitely NOT a Prairie or a Peregrine. When it perched and the coloring and wing projection and sheer size became even more apparent, we were sure we had a Gyr.
HOW DID YOU ELIMINATE SIMILAR SPECIES? WHAT WERE THEY?
The most similar species are Prairie and Peregrine Falcons. As we spent time watching the bird fly, it was obviously a falcon and so much larger than either a Prairie or Peregrine. The coloring also helped us determine it wasn’t a Prairie (no dark wing pits) and not a Peregrine (no slate blue black and no pronounced dark helmet on face).
WHAT IS YOUR EXPERIENCE WITH THIS (AND SIMILAR) SPECIES?
Jay has seen other Gyrfalcons in the wild, but this was my first one. However, we have many field observations of Prairie and Peregrine Falcons.
DESCRIBE YOUR GENERAL BIRDING EXPERIENCE
Jay: 20+ years of experience; avid birder, Tempe: 10 yrs of field experience working/surveying for raptors and in the last 5 yrs becoming more of a more serious birder.
ADDITIONAL INFORMATION (If any)
YES [photo], see attached by Jay Carlisle. Quality is poor due to digi-scoping with cell phone in bad lighting.
WERE PHOTO(S), VIDEO, AND/OR AUDIO OBTAINED FROM THIS SIGHTING?
Photo
SUPPORTING IMAGES

FIRST ROUND VOTING:

Cliff Weisse
Accept

Description and photos support the identification of Gyrfalcon.

Carl Lundblad
Accept

Good description and distant but diagnostic photo shows an enormous falcon with long wings (too long for Prairie) and distinctive face pattern.

Shirley Sturts
Accept

could not tell much from the photo but the description and comparisons of smaller falcons and possible large hawks was convincing

Jon Isacoff
Accept

The documentation is sufficient to rule out Peregrine and Prairie, noting key differences in plumage pattern and flight style. While I'd discount whether the size of single bird at distance can be very accurately judged as larger or smaller than similar species, the description of the plumage pattern and flight style are diagnostic. Additionally, the photo indicates a falcon with notably bulky structure and very long length proportionate to size of head and tail , matching nicely the profile of Gyrfalcon.

Dave Trochlell
Accept

No doubt about it, this was a Gyrfalcon.

Darren Clark
Accept

description is good. photo supports description.

Doug Ward
Accept

Excellent description with decent comparable discussion to other potential candidates. Photo indicates diagnostic structure (relatively short wings/long tail) and apparent large size – great bird!