Verification of Unusual
Rec. # 2017-43
|Scientific name:||Buteo albonotatus|
|Date:||12 June, 2017|
|Length of time observed:||~2 minutes|
|Location:||east of Cisco, between the railroad tracks and Kokopelli Trail|
|Distance to bird:||50-75yds|
|Optical equipment:||Equipment: naked eye|
|Weather:||clear but extremely windy, S-SW gusts measured by observer that morning at 50mph and 64mph by early afternoon|
|Light Conditions:||bird well lit, viewed to the north and then east with sun overhead or over my shoulder|
|Description: Size of bird:||similar to RTHA|
|(Description:) Basic Shape:||typical Buteo, broad wings and moderate tail length|
|(Description:) Overall Pattern:||very dark above and below|
|(Description:) Bill Type:||not observed|
Field Marks and
I was on top of a local high point for a cell signal, and observed the bird
below me, tacking across the wind moving west to east 20-30ft above the ground.
It was blackish raptor and very similar to a TUVU at first glance, but the
proportions were Buteo-like. The wings were broad and somewhat pointed, with
tips that appeared darker on the upperside. The tail was of typical Buteo length
and shape, not long like Accipiter or short like BLVU, and fanned into a distal
curve unlike PRFA. The bird held its wings in a distinctive V, which caused it
to teeter like a TUVU in the strong wind. This allowed me to see the equally
dark underside of the bird. Beyond the wing shape, the indication that this was
not a TUVU was the strongly banded tail, which bore wide black and white bands.
The terminal band was black, but other than a single large white band (which had
a distinct proximal edge instead of blending onto the tail base) I did not
observe other details of the tail (the
rump of the bird was blackish like the rest of the upperside). The bird continued to work around the hill south and then west below me at approximately the same distance, until it cleared a ridge and disappeared from view. I did not observe bill or foot color.
|Song or call & method of delivery:||N/A|
|Behavior:||Soaring and teetering in strong winds, wings held in a distinctive V; did not observe bird flap wings.|
|Habitat:||Arid with little vegetation, locally rugged with flat, open country to the immediate west and deep canyons of Colorado River to the immediate east.|
were they eliminated:
Very similar to TUVU in overall dark color and
wings held in a V, but wings came to a point instead of jagged 'fingertips;'
tail was fan-shaped and bore strong black and white bands.
Very similar to adult COBH in overall dark body color and tail pattern, but differed in proportions with wings not nearly as broad, somewhat pointed, and held in a distinctive V; tail appearing relatively longer and more typically Buteo (not like BLVU).
Smaller and with less massive proportions than GOEA (locally common), with bird observed close enough to judge size; though bird was blackish, white tail bands are inconsistent with adult GOEA and the bird lacked any white wing patches (observed as very dark).
Dark-morph RLHA: the underside of the wings were dark on this bird, instead of dark with a wide white perimeter. The tail was observed from above and the wide white band was clearly visible.
Dark-morph SWHA: this bird was blackish above and below with no obvious contrast in tone of body feathering, unlike shades of brown and buff. Bold, wide black and white tail bands inconsistent with SWHA.
Harlan's RTHA: tail pattern differed, with wide black terminal band and (at least one) sharply bounded white band.
Dark-morph BWHA: similar in color and proportions (especially tail pattern), though wings of this bird were held in a strong V and underside lacked sharp tone contrast. Habitat quite inconsistent with BWHA.
this & similar species:
|I have not encountered this species before (or COBH), but have lots of experience with TUVU and GOEA which are the local species most similar to this bird.|
|References consulted:||Several phone apps immediately following the sighting (Sibley, Audubon, iBird), and Sibley Guide to Birds (1st and 2nd editions).|
|Description from:||Notes taken at the time of the sighting|
|Observer's address:||10710 Sun Ridge Rd. Goshen, KY 40026|
|Observer's e-mail address:||**|
|Other observers who independently identified this bird:|
|Date prepared:||21 June 2017|
|Additional comments:||I am a paleontologist and had been working in the area for two weeks. The weather had been extremely windy from the S-SW for several days prior to sighting, with a dust storm blowing in by the end of that day. I measured sustained winds well over 30mph all that morning, with a measured gust in early afternoon at 64mph (though likely not the strongest).|