Verification of Unusual Sight Record
For Utah

Rec. # 2005-47

Common name:

Black-throated Blue Warbler

Scientific name: Dendroica caerulescens
Date: 10/6/2004
Time: approx 10:00am
Length of time observed: less than 1 minute
Number: 1
Age: Adult
Sex: Male
Location: South Fork/Big Springs Park [Provo Canyon]
County: Utah
Latilong:  -11.52740, 40.328
Elevation: 6000ft
Distance to bird:  less than 25 feet, more than 12 feet (I focused my binoculars)
Optical equipment: Swift Audubon 8.5x44
Weather: Sunny
Light Conditions: Under canopy
Description:        Size of bird: small, warbler sized
(Description:)       Basic Shape: a bit skinnier than the R-c Kinglet it was near
(Description:)  Overall Pattern: blue on head and back, black mask/bib and white underparts (& wing spot)
(Description:)            Bill Type: insectivore, small, thin & pointed
Field Marks and
Identifying Characteristics:
The bird was identifiable without optics when it appeared. It was about the same size or perhaps a bit larger than the nearby R-c Kinglet. Its blue back and contrasting white wing spot were the
first solid field marks seen. Once I held up my binoculars, I clearly saw a black mask and bib contrasting with the white underparts and the blue back. The white wing spot was also observed through binoculars. The bill was small but I did not note its color. Also did note color of legs since other field marks were quite conclusive.
Song or call & method of delivery: No song or call heard.
Behavior: Foraging about 6-8 ft from the ground.
Habitat: Young Gambel's oak, aspen adjacent to full-grown narrow-leaved cottonwood riparian.
Similar species and how
were they eliminated:
The male is unmistakable and other "blue birds" lack the black, white and blue pattern described. Chickadees have a black bib but show no blue coloration and lack a white wing spot.
Previous experience with
this & similar species:
I have a great deal of experience with this species and have seen it at least 50 times in Massachusetts and New York State both during migration and on the breeding grounds. Conducted nesting bird surveys in adjacent habitat.
References consulted: Sibley Guide, Warblers (Kimball, Dunn & Garrett), Warblers of the Americas (Curson,Quinn, and Beadle)
Description from: From memory
Observer: Matthew J. Williams
Observer's address: 627 N 600 W #10, Provo, UT 84601
Observer's e-mail address:
Other observers who independently identified this bird: Amanda Williams (see comments)
Date prepared: 10/31/2005
Additional material:  
Additional comments: Amanda Williams, my wife (also present & saw the bird), having never seen a Black-throated Blue Warbler before noted the white marking on the wing and overall coloration of the bird to make an ID (per discussion shortly after the sighting)

Detailed Location: From the National Forest Access (Big Springs Park) in South Fork Canyon, we parked in the upper lot. The bird was seen nearly 0.5 mile up the fire road (not the singletrack). On the way up, you will cross the creek twice and, about 2-300 feet before the big meadow, you will see a large narrow-leaved cottonwood on the right with a dead branch hanging over the road. The bird was seen on the left side of the trail (when facing up the trail). It was with R-c Kinglets and I think I heard Yellow-rumpeds as well. It headed off farther to the left (SW)
and out of sight.