Verification of Unusual Sight Record
For Utah

Rec. # 2011-72


Common name:

Lesser Black-backed Gull

Scientific name: Larus fuscus
Date: December 9-10, 2011
Time: late afternoon and miday
Length of time observed: 30-60 minutes cumulative
Number: 1
Age: adult
Sex:  
Location: Location: Quail Creek State Park
County: Washington
Latilong: 19
Elevation: ~ 920 m
Distance to bird: 30-100 m
Optical equipment: 20-60x scope
Weather: clear and calm to windy
Light Conditions: late afternoon sun on 12/9 and midday direct sun on 12/10
Description:        Size of bird:  
(Description:)       Basic Shape:  
(Description:)  Overall Pattern:  
(Description:)            Bill Type:  
(Description:)                              
Field Marks and
Identifying Characteristics:
Adult Lesser Black-backed Gull first observed swimming a few meters off of rock bar used by roosting gulls at Quail Creek Reservoir. Several thousand Ring-billed Gulls, a first-winter Thayer s Gull, and a first-winter Herring Gull were also present, however, the black-backed gull was only loosely associated with the large gull flock; very wary perching on buoys rather than shoreline and flying well out onto reservoir when approached by fisherman along shoreline.
  
Also present the morning of December 10th.
  
Description:
  
Medium sized dark backed gull, larger than nearby Ring-billed Gulls. White headed gull with yellow legs and dark gray mantle. Head and undersides white with smudgy brown streaking on face around eye and and extending to nape. Pale eye, and relatively straight yellow bill with red gonydeal spot. Folded wings dark gray with prominent white crescent and secondary skirt, black primaries with white tips. White tail.
(see photos)
Song or call & method of delivery: na
Behavior: see above
Habitat: open reservoir
Similar species and how
were they eliminated:
Distinguished from most large white-headed gulls by dark back and yellow legs.

Distinguished from Yellow-footed Gull by smaller size and dusky markings on head (face and nape).
Previous experience with
this & similar species:
yes
References consulted:  
Description from: Notes made later
Observer: Rick Fridell
Observer's address: Hurricane, UT
Observer's e-mail address: rfridell@burgoyne.com
Other observers who independently identified this bird:  
Date prepared: 12-31-2011
Additional material: Photos
Additional_Comments: description copied from field notes.