Sighting Record for Utah

Common name:	Eastern Bluebird
Scientific name:	Sialia sialis
Date:	12/14/2019
Time:	1:30 PM
Length of time observed:	5 minutes
Number:	1
Age:
Sex:	Male
Location:	Virgin River, north of Grafton
County:	Washington
Latilong:	37.16875, -113.08132
Elevation:
Distance to bird:	Varied - 10 to 50 yards
Optical equipment:	8x42 binoculars & 500 mm lens
Weather:	Cloudy, calm
Light Conditions:	Fairly dim due to cloud cover
Description: Size of bird:
(Description:) Basic Shape:	Small thrush
(Description:) Overall Pattern:	Blue/rufous/white
(Description:) Bill Type:	Small, thin
(Description:) Field Marks and Identifying Characteristics:	Observation details: While birding the area north of Grafton during the Zion Christmas Bird Count, we noticed a bluebird perched on a fallen cottonwood tree that was draped over the Virgin River. We almost dismissed it as a western bluebird, but upon closer examination we noticed the bright white belly. As we approached, it flew down towards the river and out of view, but it soon returned to a higher tree branch where I was able to get several decent photos. It eventually flew away from the river, and landed on a Russian olive where I got a distant view of its back. It appeared to be foraging with a flock of house finches. It then flew again; this time out of sight and we were unable to relocate it, but we didn't spend much time trying. Interestingly, this was the only bluebird we saw all day. Description: Small thrush with a rufous breast, flanks, throat, and sides of neck. It had a white belly and undertail coverts (starkly contrasting with the rest of the bird). Its back, head, wings, and tail were almost entirely blue, with darker wingtips. Relatively short and thin bill. (see photos)
Song or call & method of delivery:	Silent
Behavior:	Foraging along Virgin River. Quite active; flew and landed several times while observing.
Habitat:	Cottonwoods, Russian olives, and other riparian vegetation associated with the Virgin River near Zion.
Similar species and how were they eliminated:	Western bluebird: Males would show at least of tinge of blue on belly and a blue throat (vs. clean white belly of eastern and rufous throat). Westerns would not have rufous wrapping around the sides of their neck. However, they do show rufous on their scapulars, which was lacking on the bird we observed. Mountain bluebird: Would never show as much rufous as the bird we observed. Males are more uniformly blue than westerns and easterns and generally have a lighter "sky blue" plumage.
Previous experience with this & similar species:	Fairly limited experience with eastern bluebirds. However, I observed several of them earlier this year while visiting northern Illinois. Western bluebird: Have observed on many (dozens) of occasions and probably hundreds of individuals. Mountain bluebird: Have observed on many (dozens) of occasions and probably hundreds of individuals.
References consulted:	Sibley App and Western Field Guide http://hawksaloft.org/2016/03/09/differentiating-western-and-eastern-bluebirds/
Description from:	From memory From photo(s) taken at the time of the sighting
Observer:	Mike Schijf
Observer's address:	433 East 1050 South APT 3
Observer's e-mail address:	**
Other observers who independently identified this bird:	John Schijf
Date prepared:	12/15/2019
Additional material:	Photos
Additional comments: