Documentation of Iceland Gull

Observer Information

Reporter:  David Dowell  3721 Staghorn Dr,   Longmont, CO  80503
Other Observers:  Kathy Mihm-Dunning, Joey Kellner, Dick Schottler, Alec Hopping, Nena Torres, Dean Shoup, Charlie Lawrence

Species, Date, Time and Location Information

Species:  Iceland Gull
First Date/Time:  3/8/2015 4:30:00 PM
Last Date/Time:  3/8/2015 4:50:00 PM
Duration (total time in view):  20 minutes
County:  Washington
Specific Location:  Prewitt Reservoir State Wildlife Area
Number:  1
Age:  Immature
Sex:  Unknown
Plumage:  Breeding


large reservoir with combination of ice and open water

Viewing Conditions

Optics:  scope, binoculars, camera
Distance:  as close as 100 feet
Light:  bright sun

Description of the Bird

The Iceland (Kumlien's) Gull was observed among a variety of other gulls feeding on thawing fish.  Overall size was between that of Ring-billed and Herring Gulls.  Legs were pale pink.  Compared to Herring Gulls, this gull had a smaller and rounder head.  The eye was dusky (i.e., darkish rather than completely dark).  The yellow bill, with a red gonys spot, was slender but longish for Kumlien's Gull, possibly indicating a male bird.  The pale gray back was paler than that of the Ring-billed and Herring Gulls.  The head and neck were pure white with no smudging.

Most notably, the gull had pale primaries.  When the gull was walking around, the apparent color of the folded primaries depended on what direction it was facing.  When the gull was facing the sun, the primaries appeared to be medium gray (in contrast to the slaty gray / black of the other gulls).  In other circumstances, the primaries appeared much paler.  Gray color was nearly undetectable on the otherwise all-white undersides of the wings.

Although the gull had an adult-like bill, other characteristics suggested a third-cycle gull, specifically some dusky color on the tail and a lack of white tips on P8 and P9.  In the attached photo of the spread wings, P10 (mirror near tip), P7 (white tip), and P6 (white tip) have adult characteristics, whereas P8 and P9 have immature characteristics.   

Similar Species Discussion

The observed Iceland Gull was similar to Thayer's Gull in body structure and bill, but the primaries were much too pale for Thayer's Gull.  Also, Thayer's Gull would typically have deeper pink legs and a darker mantle.  Other adult gulls with gray primaries -- Glaucous-winged and Glaucous x Herring -- would have had stocky appearances and stout bills, not characteristics of the observed gull.  Glaucous x Herring would have had a pale eye, unlike the observed gull.

Resources Used

Howell and Dunn Gulls of the Americas
Sibley Guide to Birds

Previous Experience

many years of experience among our group observing gulls, including Iceland Gulls of various ages


Review of photos

Date Documentation Submitted

12/31/2015 8:37:00 PM
Click left or right edges of photos to move through all; click outside image to close

Location Map

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