ML313549221

Age and sex

Adult, Unknown sex - 1

Media notes

our presumed Thayer's gull is fourth bird from left at upper left of image. we propose this gull to be an adult in - or developing - definitive alternate plumage

Observation details

EDITED 22 MAR 2021: originally entered as Iceland Gull, but after consultation with a much better birder, we leave this entry as originally written, but doubt this is anything but a herring gull showing fresh plumage or glistening differently in sun and sun reflected on water than nearby gulls. see "details" above at herring gull. we tentatively assign here a gull with darker mantle and upper wings with white spots on primary tips to Iceland Gull (Thayer's) Larus glaucoides thayeri. we have seen in flight several times a gracile "herring gull" with apparently darker wings and mantle than other herring gulls. this is our best view (and not very good) that prompts consideration as a Thayer's gull now subsumed into Iceland gull. we realize it may be hard to determine in this image if this gull is smaller or more gracile than the herring gulls in the flock as might suit any of the Iceland gulls. this or another similar gull in flight shows less dark on the underwing and then only near the tip - another character to distinguish from herring gull. another character to consider is leg color. as one of a constellation of characters redder legs than typical of a herring gull might contribute to identification as Thayer's gull. leg color by itself is not a defining character. perhaps the eye does appear dark rather than pale, but again the camera may distort reality. our best match to this gull is an image at Macaulay Library at < https://macaulaylibrary.org/asset/52890551 >. we also accept that the camera often distorts colors, contrast, and perspective. this gull may look darker than the others merely because it is closet to the dark river water rather than with a background of glossy ice. we concede that Thayer's gull is highly unlikely in Maine based on near absence of other state records. even so, Thayer's is less of an incidental or erratic in all the neighboring states and provinces. we now (5 MAR 2021) have side view that suggests a higher angle at base of bill and forehead - a feature suggested by some observers as a minor distinction between some forms of Iceland gull and the flatter headed and bill of typical herring gull. advice welcomed [ and both offered and accepted a few days later]

Additional species

• Herring Gull Larus argentatus

Technical information

Model

Canon PowerShot SX230 HS

ISO

125

Focal length

70 mm

Flash

Flash did not fire

f-stop

f/5.9

Shutter speed

1/500 sec

Dimensions

4000 pixels x 3000 pixels

Original file size

973.06 KB