Documentation of Iceland Gull
2017-012

Observer Information

Reporter:  Steven Mlodinow  530 Peregrine Circle,   Longmont, CO  80504-8806
E-mail:  smlodinow@gmail.com
Other Observers:  David Dowell and Nick Moore, who agreed with ID

Species, Date, Time and Location Information

Species:  Iceland Gull
First Date/Time:  3/4/2017 1:00:00 PM
Last Date/Time:  3/4/2017 1:25:00 PM
Duration (total time in view):  10-15 minutes
County:  Weld
Specific Location:  Black Hollow Reservoir
Number:  1
Age:  Immature
Sex:  Unknown
Plumage:  Other/Unknown

Description of the Bird

A number of gulls moved from mid lake to near shore. As this was happening, I spotted a much paler gull. We watched the bird for a goodly portion of the 25 minutes the bird was in view.

While sitting on water: back and folded wings of same darkness, a rather pale grayish/brownish, much paler than any nearby immature HERG and paler than adult HERG or RBGU. The back appeared more grayish, the wing more brownish, though this was subtle. The primaries had broad whitish edging. The head was white, or near white, with a hint of dusky smudging near eye. Eye looked to be dark, though nearly impossible to be certain. The bill was all black, or very nearly so. The chest and sides seemed off-white (pale brown?) whilst bird on water. The bird was between RBGU and HERG in size, with a nicely rounded head and relatively narrow and short bill. 

In flight, the wings seemed a bit browner, the back a bit grayer, but darkness equivalent. There was not even a trace of secondary bar. Two or three of the outer primaries had a narrow dusky line on the outer web. Given that much of the p10 is often not visible, I can not say what the pattern on that specific feather was. The tail was rather pale gray or brownish gray, concolorous with the back. There uppertail coverts were whiter than back or tail. The underparts, when bird was in flight, seemed nearly white (or white).

Similar Species Discussion

Thayer's Gull: Even at this time of year, I'd expect bird to be darker mantled and with more contrast, especially secondaries, primaries, and tail. This bird did not seem overly worn or faded. The smallish size and shape favors ICGU (Kumlien's Gull) over THGU, but overlap nearly complete. 

Glaucous Gull: Larger, pale base to bill 

Resources Used

None

Previous Experience

Moderate Iceland Gull and Glaucous Gull, extensive with Thayer's Gull.

Notes

Notes made AFTER observation

Materials Available





No files uploaded.

Date Documentation Submitted

3/5/2017 5:58:00 PM

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