Verification of Unusual Sight Record
For Utah

Rec. # 2004-27

Common name:

Yellow-throated Vireo

Scientific name: Vireo flavifrons
Date: September 29, 2004
Time: 9:15 A.M. - 10:30 A.M.
Length of time observed: about 30 Minutes
Number: 1
Location: Provo River Parkway. About a couple ‘blocks’ upstream from the Provo center street bridge, near a the pipe that sprays water next to the trail.
County: Utah
Latilong: 6
Elevation: 4600'
Distance to bird: As close as 15 feet up to about 40 feet.
Optical equipment: 8x42 binoculars. (Wind River Pinnacles)
Weather: Partly cloudy, calm.
Light Conditions: Very shady thick grove of trees. Occasionally backlit but most of time in great soft light.
Detailed description of bird: Clean yellow on chest and throat.
Greenish head and body.
Yellow ‘spectacles’.
Gray wings with two white wingbars.
White belly and undertail.
Gray tail feathers.

The bill was gray and ‘vireo shaped’ thicker and blunter than a warbler with a slight hook.

The yellow on the throat began at the base of the bill, was bordered on both sides by greenish auriculars and extended down the breast to a
little past the bend of the wing (on perched bird). There was a slight greenish wash that came into the yellow a little at the bend of the wing.

There was a yellow stripe from the bill to the eye over the lores and a yellow eyering around the eye broken in front of the eye with a little green. The eye was black. (The lores didn’t look as dark as shown in the Sibley guide.)

The crown, auriculars, nape and mantel were a greenish color similar to the green on the back of a Wilson’s Warbler. This green washed a little onto the sides of the yellow chest. The green auriculars were separated from the yellow throat sharply enough the give the vireo a ‘hooded’
look but not so sharp as to make a sharp line between the two colors.

The wings were gray with two bold, white wingbars. The wingbars sharply contrasted with the gray of the wing. The tail was all gray above and
below and compared to the nearby Yellow-rumped Warblers the tail was short, square, and a little wider.

The belly and undertail coverts were clean white from the end of the yellow on the breast to the tail except for a pale gray wash on the flanks that was only seen in the best lighting conditions.

The bird also looked stockier than the nearby yellow-rumps.

I never got a good look at the rump.
Song or call & method of delivery: None
Behavior: The bird would move around through the foliage of the trees and pick bugs (I think they were bugs, they were kind of flat and roundish like a sunflower seed. Maybe some kind of scale insect) from off the leaves and twigs then would carry the food to a more open spot and take a few seconds to eat it. The birds movements were ‘vireo like’ (more deliberate and slow than the Yellow-rumped Warblers in the area).
Habitat: Riparian. Dense large cottonwood, willow, and boxelder trees with partly open understory next to a slow flowing Provo River.
Similar species and how
were they eliminated:
No other vireo has yellow throat, chest and spectacles with white undertail coverts and belly.

Pine Warbler has thinner more sharply pointed bill, a pale neckpatch, White on the underside of tail (outer tail feathers) and blurry green
streaking on flanks.

Orange-crowned Warbler has thinner bill, yellow undertail coverts and no white wingbars.

American and Lesser Goldfinches have thicker bills, no spectacles or notched tail and just look much different.
Previous experience with
this & similar species:
This was the first time I’ve ever seen a Yellow-throated Vireo.
I have seen Pine warblers in Maine and Massachusetts but I’m not extra familiar with them.
I am very familiar with some other vireos such as Warbling and Plumbeous.
References consulted: The Sibley Guide to Birds.
Description from: Notes taken at time of sighting
Observer: Eric Huish
Observer's address: 850 East 100 North Pleasant Grove, UT 84062
Observer's e-mail address:
Other observers who independently identified this bird: Milton Moody
Date prepared: September 29, 2004    (General Public)
Additional material:  
Additional comments: