Verification of Unusual
Rec. # 2012-04
Lesser Black-backed Gull
|Scientific name:||Larus fuscus|
|Length of time observed:||45 minutes|
|Location:||Alfalfa field approximately 4000 N and 1450 W in Pleasant Grove (South of Deerfield Elementary in Cedar Hills)|
|Distance to bird:||Approximately 30 yards at times|
|Optical equipment:||Cabela's XT 8x42 Binoculars, Nikon D5000 Camera with 300mm f4 AFS lens with 1.4x teleconverter (420mm)|
|Light Conditions:||Very good for photography|
|Description: Size of bird:||Appeared slightly longer (more slender) than the California Gulls around it|
|(Description:) Basic Shape:||See photos|
|(Description:) Overall Pattern:||Mantle slightly darker than California Gulls next to it, slight streaking/spotting on crown and the back and sides of neck. Dark primaries had a single white spot at tip when flying. See photos|
|(Description:) Bill Type:||deep yellow for the most part with bright red on the lower mandible and some black on top mandible and bording the red on lower mandible. See photos|
Field Marks and
|In addition to comments above: Yellow iris and yellow legs|
|Song or call & method of delivery:|
|Behavior:||Was feeding with about 300 California Gulls yet it did not really interact with the other gulls. It moved about independently. It was much more skittish than the California Gulls when I approached.|
were they eliminated:
Black-tailed Gull would be way out of range. My adult bird did not have a black
band on the tail. Black-tailed also has red on upper and lower mandibles. LBBG
does not have red on upper mandible.
California Gull would have dark iris, not yellow. This gull also had a darker mantle than all the California Gulls around it. This gull also had a single white spot in the wing tip when flying not multiple white tips seen in California Gulls.
Kelp Gull would be way out of range and show very dark mantle.
Ring-billed Gull also has yellow legs and pale iris, but it is smaller than a California Gull and does not have red on its bill.
Western Gull would have pink legs, not yellow.
Yellow-footed Gull would be way out of range, would dwarf the California Gulls where the LBBG seemed only slightly larger, would have brighter yellow in the legs, and have a bulkier bill.
Yellow-legged Gull would be way out of range, would dwarf the California Gulls and have a mantle color more similar to the California Gulls, not the darker gray of the LBBG.
this & similar species:
|Recall seeing LBBG at Farmington Bay during a Utah County Birders field trip.|
|References consulted:||Sibley Guide and sent photos to Kris Purdy and Erich Huish for review.|
|Description from:||Notes made later|
|Observer's address:||3499 N 1270 W, Pleasant Grove, Utah 84062|
|Observer's e-mail address:||firstname.lastname@example.org|
|Other observers who independently identified this bird:|
|Additional_Comments:||A link to photos has been submitted to Milt Moody.|