Verification of Unusual Sight Record
For Utah

Rec. # 2010-36


Common name:

Lesser Black-backed Gull

Scientific name: Larus fuscus
Date: 05-22-09
Time: 1900- 2015
Length of time observed:  ~ 60 minutes
Number: 1
Age: first cycle (first-spring)
Sex:  
Location: Sand Hollow State Park
County: Washington
Latilong: 19
Elevation: 940
Distance to bird: 20-50 m
Optical equipment: 10 x 42 binoculars, 20-60x scope
Weather: clear calm
Light Conditions: direct afternoon sunlight
Description:        Size of bird:  
(Description:)       Basic Shape:  
(Description:)  Overall Pattern:  
(Description:)            Bill Type:  
(Description:)                              
Field Marks and
Identifying Characteristics:
On my way back from the Hurricane Fields, I drove the outer loop around Sand Hollow State Park. I noticed a very large, dark-mantled gull on the beach area of the park. The gull stood out in a small flock of California and Ring-billed Gulls, even at a great distance between the road and water s edge. I stopped and scoped the gull long enough to conclude it was a significant sighting and one of the larger dark-mantled gulls. I continued home and picked up Kristen and Rob Dobbs who was visiting. Kristen, Rob and I returned to Sand Hollow and quickly relocated the gull around 7:30p. We were able to study it in good light for 45 minutes or so as it worked it s way along about a mile of the lake shore. I managed photos of it perched and in flight. After extensive study, we were able to conclude the gull was either large Lesser Black-backed Gull or a Kelp Gull.

Description:
Large dark-mantled first-cycle gull, considerably larger and bulkier than nearby California and Ring-billed Gulls (see photo A). Large black bill with slight pale tip. White head, nape, throat, and neck with sparse dark streaking, heavier around eye. Underparts mostly white with heavier streaking than head and neck. Upperparts and mantle dark brown and black with recently molted feathers on back and wings much darker (black) than older feathers. Wings very dark overall, with thin white trailing edge on secondaries. Primary tips all black. Molt pattern in wings visible in flight photos. Base of tail white with black vermiculations and black band on tip. Legs and feet pink.
(see photos)
Song or call & method of delivery: na
Behavior:  
Habitat: shoreline of large reservior
Similar species and how
were they eliminated:
Nearly identical to a first-cycle (early summer) Kelp Gull, however, according to Alvaro Jaramillo, Kelps hae a more extensive dark tail and by the first spring have more darker and more contrasting mantle feathers.

Therefore, this first-cycle gull appears to be a large Lesser-blacked Gull. Although it is much larger and stockier overall with a larger and heavier bill than other Lesser-blacked Gull I've seen. Some folks have speculated it may be of the Asian Heuglin s group of LBBG (which also have an early molt), however, currently this can't be proven and is much less likely than other LBBG's.
Previous experience with
this & similar species:
familiar with LBBG, however, this bird is unique from others I've studied
References consulted: Paul Lehman, Martin Meyers, and Alvaro Jaramillo
Description from:  
Observer: Rick Fridell
Observer's address: Hurricane, UT
Observer's e-mail address:  
Other observers who independently identified this bird: Kristen Comella and Rob Dobbs
Date prepared: 10-03-10
Additional material: Photos
Additional_Comments: Information above copied from field notes written following the sighting. I solicited comments and help from Alvaro Jaramillo, Martin Meyers, and Paul Lehman. A similiar large apparent LBBG type gull visited Virginia Lake in Reno, Washoe Co., NV in winter 2007/08.