31 January 2022

January 2022 Quiz

 

January. California. 

Age: This is an apparent large four-year gull. The primary tips are decidedly pointed, suggesting 1st cycle. 

Identification: The plumage aspect immediately invites thoughts of a white-winged gull. The upperparts are uniformly pale throughout, with little contrast throughout the tertials and primaries. The large powerful bill and beady eye call to mind Glaucous-winged Gull. Glaucous Gull is ruled out by bill pattern, but also, due to the plainer upperparts which tend to be more patterned in Glaucous. Iceland Gull has a proportionally larger eye that's more centered on the face, along with a slimmer bill. 

Our January 2022 quiz bird is indeed a Glaucous-winged Gull.

1st cycle Glaucous-winged Gulls are sometimes found with this contrastingly pale white head and neck, against a plain grayish-brown body. It has been suggested that such a head pattern may be due to bleaching or the onset of the 1st prealternate molt. But such birds with white heads can be found in young juveniles in August, and so it appears this "look" is simply normal variation.