ML471309751

觀察細節

Possible hybrid or backcross. One of two individuals seen here throughout the following week. Most features fitting California Gull: size between Ring-billed and Herring (this individual is smaller, closer to RBGU in size), noticeably darker upperparts, dull yellow legs, CAGU wingtip pattern, relatively small head and neck. Intermediate features associated with Herring: iris more pale than CAGU (noticeable in field), orbital and gape orange (seen from closeup flight photos). This individual was seen feeding two juveniles on this day and on a future visit. The juveniles appeared indistinguishable from Herring Gull juveniles (primary pattern), probably smaller in size but hard to say.