Verification of Unusual Sight Record
For Utah

Rec. # 2011-08b
 (submitted as #2011-14)

Common name:

Western Gull (2nd cycle)

Scientific name: Larus occidentalis
Date: 18 Feb 2011
Time: 10:15am
Length of time observed: 90 minutes
Number: 1
Age: 2nd cycle
Location: Farmington Bay WMA, Unit 1
County: [Davis]
Distance to bird: see photos. 100 feet to 300 feet, approx
Optical equipment: Swarovski 65mm, 25-45x eyepiece
Weather: high overcast, no rain
Light Conditions: fair to good
Description:        Size of bird: larger than Herring Gull
(Description:)       Basic Shape: Stout
(Description:)  Overall Pattern: see photos
(Description:)            Bill Type: Stout without dramatic gonydeal angle
Field Marks and
Identifying Characteristics:
See photos
Song or call & method of delivery:  
Similar species and how
were they eliminated:
The main confounder here would be GW x Western Gull. SB Gull would have darker back, pale inner panel to primaries, etc. The short wings and stout bill eliminate species such as Cal Gull and LBBG (as do other marks). GW x Western Gulls outnumber pure adults of both species in Everett, WA (where I lived for 18 years, immediately before seeing this bird. I was en route to my new digs in Longmont, CO), and are abundant. Hybrids should show a pale panel on inner primaries, paler primaries, especially on uppersurface, and a paler back. In WA, I'd regularly see probable hybrids at either end of the spectrum that made me wonder: GW or Hybrid? or Western or Hybrid? This bird is too dark and well marked to fit into the latter category, and in my experience, is quite typical of Western Gull.
Previous experience with
this & similar species:
see above
References consulted: none
Description from: Notes made later
Observer: Steven G Mlodinow
Observer's address: 1522 Venice Lane, Longmont, CO 80503
Observer's e-mail address:
Other observers who independently identified this bird:  
Date prepared: 25 February 2011
Additional material: Photos
Additional_Comments: Notes written same evening; no guide consulted re: this bird.