Verification of Unusual
Sight Record
For Utah
Rec. # 2008-32
Common name: |
Lesser Black-backed Gull |
Scientific name: | Larus fuscus |
Date: | 5 Nov 2008 |
Time: | 2:40 PM |
Length of time observed: | about 45 minutes |
Number: | 1 |
Age: | 3rd or 4th winter |
Sex: | Unknown |
Location: | Logan |
County: | Cache |
Latilong: | 3. Logan |
Elevation: | about 4500 feet |
Distance to bird: | 10-30 yards |
Optical equipment: | Nikon Monarch 10x42 binoculars, Nikon 20x Sky and Earth spotting scope, Verizon/LG 1.3 megapixel camera phone |
Weather: | Cold, about mid-30s F. No precipitation. Recent storm had passed thro |
Light Conditions: | Overcast, mostly bright, occassionally direct sunlight for brief periods |
Description: Size of bird: | About the same size as or slightly larger than nearby California Gulls |
(Description:) Basic Shape: | Long gull shape, long neck |
(Description:) Overall Pattern: | Dark slaty-gray mantle and wings, white belly, black primaries when folded with small white apical tips, sparse but extensive smudging on the head and neck, smudging concentrated under and around eye. |
(Description:) Bill Type: | Yellow bill with bright orange-red gonydeal spot, some smudgy black behind the gonydeal spot in an incomplete ring around the bill, not meeting at the top of th |
(Description:)
Field Marks and Identifying Characteristics: |
This gull stood out from the California, Ring-billed, and Herring Gulls around
it due to its distinctly darker mantle. It was about the same size as the
California Gulls around it but its head seemed to rise above them due to a
longer neck than that of the Californias. It had crisp streaking that was spread
throughout the head and nape and a bit down to the upper sides of the breast.
The streaking was concentrated in a half-circle under the eye, giving the
impression that the bird had been punched in the eye. The eye was pale. The legs
were bright yellow, brighter than the legs of the California Gulls and about the
same color or perhaps a bit brighter than those of the adult Ring-billed Gulls.
The folded primary tips were mostly black with very small apical tips. This may be a third-winter bird, not an adult, because of the black smudging behind the orange-red gonydeal spot on the bill and because of the reduced white mirrors in the primaries. Alternatively, this bird may still be molting into fourth-winter plumage from third-summer. It seemed to be having some molting problems, as all of the outer secondaries were missing. The tail was pure white, which can indicate third- or fourth-winter birds. (see photos) |
Song or call & method of delivery: | None known for certain to come from this individual. |
Behavior: | Loafing among hundreds of California Gulls and a handfull of Ring-billed Gulls and Herring Gulls. Stole food from other gulls periodically or found its own food in the water |
Habitat: | "Shorebird Playa" at the Logan River Wetlands, known locally as "Sue's Ponds". Shallow muddy pond designed for shorebird habitat. Surrounding area is largely agricultural, with the Logan Landfill very near to the east. |
Similar
species and
how were they eliminated: |
Great Black-backed Gull: Much larger than this bird, which was just slightly
larger than the California Gulls and much smaller than the Herring Gulls around
it. Pink legs in adult Great Black-backed Gulls do not match the bright yellow
legs of this individual. Extensive streaking in the nape of this bird is also
not typical for Great Black-backed Gulls. Herring Gull: This bird was too small for a Herring Gull, had a mantle that was too dark, and had legs that were yellow, not pink. Western Gull: Again this bird was too small for a Western Gull. Also, the legs of this bird were bright yellow, in contrast to the pink legs of a Western Gull. The extent of smudging in the head and neck is also not seen in Western Gulls. California Gull: There were many California Gulls present for direct comparison. The size of this bird was about the size of a California Gull (slightly larger than California), but its mantle was noticeably darker. California Gulls have dark eyes, and this gull had pale eyes. Yellow-footed Gull: This bird was not large enough for a Yellow-footed Gull, being only slightly larger than a California Gull. It's bill was not heavy enough and it had too much streaking in the head and nape. Slaty-backed Gull: This bird was again too small for a Slaty-backed Gull, and had yellow, not pink, legs. |
Previous
experience with this & similar species: |
This is my first sighting of a Lesser Black-backed Gull. |
References consulted: | The Sibley Guide to Birds, Howell and Dunn's Gulls of the Americas, National Geographic Field Guide to Birds of Western North America |
Description from: | From memory |
Observer: | Ryan P. O'Donnell |
Observer's address: | 1098 Crescent Drive, Logan, UT |
Observer's e-mail address: | Ryan@biology.usu.edu |
Other observers who independently identified this bird: | Jason Pietrzak and Anne Winters |
Date prepared: | 6 Nov 2008 |
Additional material: | Photos |
Additional Comments: | I am submitting with this record two photos that I took with my cell phone through my spotting scope. Jason Pietrzak has much better photos that he will be submitting with his report. |