It was cold here Saturday afternoon, March 6. The Gulls were sopping up the sun on the Blue Hill Harbor Dock pylons, not inclined to move when a lens was pointed in their direction. It was a good time to try to work on identifying the plumage transitions from immature to adult Gulls.
Here, you have a four-year adult Herring Gull, our most common Gull. It’s notable by its white body, gray wings and back, red spotted lower bill, yellow eye, and pinkish legs.
Herring and some other larger Gulls have a four-year transition to mature plumage, with different phases each year.
These differing immature Herring Gull plumages often are difficult to identify as to year, especially since there is extensive variation in them due to interbreeding and other factors. However, my best guess for this Gull is that it’s a three-year Herring Gull:
But, as usual, I’m not sure. Some of you black-belt birders may know what it is with certainty. (Brooklin, Maine)