Verification of Unusual Sight Record
For Utah

Rec. # 2009-11

Common name:

Yellow-billed Loon

Scientific name: Gavia adamsii
Date: 18 May 2009
Time: 8:30 to 9:00 AM
Length of time observed: about 30 min.
Number: 1
Age: adult
Location: Rockport Reservoir
County: Summit
Distance to bird: varied from about 40 feet to 500 feet
Optical equipment: 8 x 42 binoculars, 20-60 x 80 Kowa scope and Nikon Coolpix camera (for digiscoping)
Weather: Clear
Light Conditions: The bird was backlit most of the time except when it got very close.
Description:        Size of bird: Larger than nearby Common Loon
(Description:)       Basic Shape: Loon shaped
(Description:)  Overall Pattern: black and white
(Description:)            Bill Type: very large, sharp
Field Marks and
Identifying Characteristics:
The elongated head was black with a prominent bump on the forehead and a long sharp whitish yellow bill that was straight on the upper edge and gradually tapered up at the end of the lower mandible.  The neck was also black with white spots on the throat and tapered patches of vertical white stripes on the sides.  The Breast was white.  The rest of the body was black with a a striking checkered pattern on top with white spots toward the sides.
(see photos)
Song or call & method of delivery: none heard
Behavior: It was very active diving and moving around the reservoir.
Habitat: Deep mountain lake
Similar species and how
were they eliminated:
The Common Loon which was also present (and was fairly close to this bird at one point) is smaller, has a dark bill that tapers from both top and bottom and has a white pattern on its throat that is more prominent than the YB Loon (from the pictures I took there seemed to be only 3 or 4 spots of white on the throat).

Other Loons don't have a black head and throat.

Previous experience with
this & similar species:
I've seen a lot of Common Loons but never a YB Loon.
References consulted: Sibley's, National Geographic
Description from: Memory, refreshed by photos
Observer: Milton Moody
Observer's address: 2795 Indian Hills Drive, Provo, Utah 84604
Observer's e-mail address:
Other observers who independently identified this bird: First seen by Tim Avery and a field-trip group the day before.  Kathy Donnell, Tom Fletcher, Sirpa Grierson and Leena Rogers saw it at same time I did and there were many others that saw it on the same day. 
Date prepared: 30 May 2009
Additional material: Photos