Verification of Unusual Sight Record
For Utah

Rec. # 2020-72

Common name:

Red-throated Loon

Scientific name: Gavia stellata
Date: November 15, 2020
Time: 10:00 am
Length of time observed: 1 hour, 45 minutes
Number: 1
Age: Presumed adult
Sex: Unknown
Location: Willard Bay State Park (west dike) accessed from Willard Spur NW Playas
County: Box Elder
Latilong: 41.377674, -112.132566
Distance to bird: 100-250 Meters
Optical equipment: Swarovski 20x60 Spotting Scope, 10x42 and 8x42 Nikon Monarch Binoculars, iPhone 6S+ (photos through scope)
Weather: Overcast, but no precipitation. Quite windy for the majority of the morning, except the last 30-40 minutes in which the wind ceased.
Light Conditions: Overcast, which worked in our favor as we were looking east towards the rising sun. No light interference.
Description:        Size of bird:  
(Description:)       Basic Shape:  
(Description:)  Overall Pattern:  
(Description:)            Bill Type:  
Field Marks and
Identifying Characteristics:
Rather small loon in non-breeding plumage seen in direct comparison with Red-breasted Mergansers and Western, Clark’s, Eared, and Horned Grebes. Similar in size to the two Aechmophorus Grebes, but had a noticeably thicker neck and thicker head. Seen diving, resting, and preening throughout observation. Gradually drifted south of our position towards the southwest corner of the reservoir.

Significant amounts of white visible along the flanks while resting, as well as on the neck. Sharp delineation between the dark gray of the hind neck and cap with the white of the throat and cheek (suggestive of an adult bird over a juvenile). The bill was silver in color and appeared to be very thin. Due to the posture of the bird, the bill was continuously held at an upwards angle. The bill itself seemed to be slightly upturned. The back appeared dark overall with small white flecks, or spotting (unlike the more extensively patterned checkering shown on Common and Yellow-billed Loons.
(see photos)
Song or call & method of delivery: Silent
Behavior: Diving, preening, and resting on open water of Willard Bay. Loosely interacting with Western, Clark’s
Habitat: Open, deep-water on west end of Willard Bay.
Similar species and how
were they eliminated:
Common Loon: Much smaller and slimmer bodied; sharp, unbroken contrast between dark neck and white throat; thin, silver, slightly upturned bill held upright in line with typical RTLO posture; significant white along the flanks while resting; Sat lower in the water than Common Loon present, although it was not compared directly.

Pacific Loon: The shade of gray (particularly on the head, or “hood”) was significantly darker than the lighter, silver gray typical of non-breeding Pacific Loons. Appeared smaller, and flatter-headed and lacking the rounded look of PALO; white in the face more extensive than expected for this species; lacked any sort of necklace across the throat; silver bill upturned and held high unlike Pacific Loon, which have a straight and slightly thicker bill; Posture also atypical for a Pacific. Extensive white was apparent across the flanks consistently - while resting, preening, or casually floating on the water.
Previous experience with
this & similar species:
Have encountered RTLO in non-breeding plumage several times before in Utah. Extensive experience with both Common and Pacific Loons, particularly in non-breeding plumage.
References consulted: Sibley Guide to Birds, Macaulay Library.
Description from: From notes taken at time of sighting
Observer: Kendall Watkins, Quinn Diaz
Observer's address: 2622 W Dry Creek Drive, Riverton,: Utah  84065
Observer's e-mail address: **
Other observers who independently identified this bird: Quinn Diaz, Mike Hearell, Taylor Abbot, Bryant Olsen, Vivian Schneggenburger, Lauri Taylor, James Hoffman.
Date prepared: November 20, 2020
Additional material: Photos
Additional comments: