01 April 2024

March 2024 Quiz

Illinois. October.

Age: The overall plumage aspects of the two big brown jobs suggest 1st cycle. The center bird is an adult-type.

Identification: The adult in the center is a Ring-billed, with what appears to be a chunkier and slightly larger 1st cycle on the left and a slightly smaller gull on the right.

Note the darker brown centers to the upperparts on the individual on the right, showing broader and more consistent pale fringes. The bill appears thinner and jet black, with paler vent region. This is a 1st cycle Lesser Black-backed Gull in complete juvenile plumage. The individual on the left has a deeper chest, a weaker pattern to the coverts and what appear to be replaced juvenile scapulars. It falls squarely in the mold of a 1st cycle American Herring Gull.