Verification of Unusual
Sight Record
For Utah
Rec. # 2019-01a
| Common name: |
Great Black-backed Gull |
| Scientific name: | Larus marinus |
| Date: | 01-13-2019 |
| Time: | 09:45am |
| Length of time observed: | 30 minutes |
| Number: | 1 |
| Age: | adult |
| Sex: | ? |
| Location: | Flaming gorge reservior, stateline cove |
| County: | Dagget |
| Latilong: | 40.9978576,-109.603538 |
| Elevation: | 6,100ft |
| Distance to bird: | 50m at closest |
| Optical equipment: | Nikon 10x 42, Vortex 20-60X Spotting scope |
| Weather: | Foggy, lite snow falling, 16F |
| Light Conditions: | poor |
| Description: Size of bird: | 30in |
| (Description:) Basic Shape: | Typical gull |
| (Description:) Overall Pattern: | black back, white head,tail and torso |
| (Description:) Bill Type: | Huge, yellow with a red spot |
|
(Description:)
Field Marks and Identifying Characteristics: |
Huge gull, noticeably bigger than a Herring Gull when they were together. Very
dark black back,huge bill with significant Gonydeal angle and a red spot on
lower mandible. Pink legs, short primary projection, pale iris with red orbital
ring, clean white head without streaking. Very distinctive. (see photos in eBird checklist) |
| Song or call & method of delivery: | none heard |
| Behavior: | Fist seen on shore, then flew to water and swam around abit, then returned to shore to loaf and preen |
| Habitat: | Large man made reservoir on Green River. Freshwater but much open water despite cold temps |
| Similar
species and
how were they eliminated: |
Lesser Black-backed would be smaller, longer primary projection, yellow
legs and have lots of streaking on head in basic plumage. Are much smaller Western Gull are usually smaller,about size of Herring, back not as dark blackish, more slaty gray.Slightly smaller bill Yellow-footed Gull perhaps most similar but have bright yellow legs Kelp Gull should be somewhat smaller, have dull greenish yellow leg sand smaller bill |
| Previous
experience with this & similar species: |
None with Great Black-backed, I've seen many Lesser Black-backed and Western Gulls |
| References consulted: | Sibley 2014 |
| Description from: | From photo(s) taken at the time of the sighting |
| Observer: | Bryant Olsen |
| Observer's address: | 84102 |
| Observer's e-mail address: | ** |
| Other observers who independently identified this bird: | First reported by Brian Maxfield on Jan. 9th. Max Malmquist and Lauri Taylor were with me |
| Date prepared: | 1-14-2019 |
| Additional material: |
|
| Additional comments: | eBird checklist: https://ebird.org/view/checklist/S51648354 |