Verification of Unusual Sight Record
For Utah

Rec. # 2021-37


Common name:

Blue-winged Warbler

Scientific name: Vermivora cyanoptera
Date: 05/18/2021
Time: 6:30 AM
Length of time observed: 110
Number: 1
Age: ASY
Sex: Male
Location:

Bonderman Field Station (Rio Mesa Field Station)

County: [Grand]
Latilong: 38.799311549913504, -109.20449961499045
Elevation: 4250
Distance to bird: Caught at the station around 610 AM. Extracted and banded.
Optical equipment:  
Weather:  
Light Conditions: Pre-dawn
Description:        Size of bird: smaller than YEWA
(Description:)       Basic Shape: warbler shaped
(Description:)  Overall Pattern: yellow body, dark wings, white wingbarks
(Description:)            Bill Type: long, thin, pointed
(Description:)                              
Field Marks and
Identifying Characteristics:
Adult male. Somewhat small warbler with a bright bright yellow face, throat, and breast, transitioning to a greenish-yellow nape and back. The bird had a thin black mask and a long black pointed bill. Wings were dark blue-gray with white wing bars on greater and median coverts. The tail was medium length (proportionally) and had three tail feathers on each side that were predominately white.
(see photos)
Song or call & method of delivery:  
Behavior:  
Habitat: Riparian habitat dominated by Tamarisk, saltbrush, rabbit brush, and new mexico privet.
Similar species and how
were they eliminated:
There aren't really any similar-looking expected species at Rio Mesa so I compared with several common warblers at Rio Mesa.

Differentiated from YEWA by a strong thin black mask, blueish wings with strong white wing bars. This bird didn't have any reddish streaking on the breast and have large white patches on the outer rects rather than large yellow patches.

Differentiated from WIWA by bright lemon yellow face, throat, and breast which is not customary for WIWA. Bird also had very strong obvious white wing bars and obvious white in the tail.

Differentiated from COYE by a significantly thinner black mask, longer tail, and large white patches in outer rects. The tail was also longer than the tail of the COYE would be.

Differentiated from YBCH by significantly smaller size thinner black mask, blueish wings, and strong bright white wing bars and white in the tail.
Previous experience with
this & similar species:
I have seen this species on its breeding range in Missouri and we caught one at a banding station in Denver five or so years ago.
References consulted: Sibley and Pyle's Guide to North American Birds
Description from: From photo(s) taken at the time of the sighting
Observer: Kyle Kittelberger, Megan Miller, Kara Beer, Becca Buschhaus
Observer's address: 21320 East 40th Ave Denver, Co 80249 
Observer's e-mail address: **
Other observers who independently identified this bird:  
Date prepared: 06/16/2021
Additional material: Photos  
Additional comments: Many photos were taken including photos of spread wing, tail, and traditional portrait.