ML79357511

Age

Not specified

Sex

Not specified

Observation details

Identification: in comparison to the numerous RB Gulls, the subject bird was much darker in plumage but nearly identical in size. Following Emanuel’s recognition of the pale rump in flight, the size comparison was the second strong clue that this bird was not a Herring Gull. In flight, Herring Gull display’s a brown rump overlain by dark barring that, taken together, does not contrast as sharply with the dark tail band, also dispalyed by this species. Herring Gull is a much larger bird and would “tower” over the Ring-billed Gulls; whereas this bird was of similar size to the surrounding RB Gulls, perhaps slightly larger. The bird was being viewed ata distance of probably 100 yards. Even at this distance, the following characters were visible: a round-shaped head, a long thin bill with a pink base and a black tip, long wings, and a dark bar on the folded wing that matched the very dark coloration of the wing tip. This effect is explained by the dark wingtips being the primary feathers and the dark bar being the greater coverts and tertilas—all visible on the folded wing. In order to get closer to the bird, we returned to the car, parked on Lakeshore Drive, turned it around and drove farther east before reparking on Lakeshore. We drove only a few hundred yards before being positioned opposite the gull flock. By the time we had walked down to the lakeshore we had closed the distance to the birds considerably. We estimate the distance to the birds at about 40 yards. Again, all of the above features were clearly visible. Now however, we could also gain a better feel for the overall plumage coloration of the bird in question. It was a marbled brown and gray, as opposed to the “muddy” diffused brown and gray coloration more typical of Herring Gulls of a similar age. Lyon obtained some poor quality digiscoped photos using an iPhone 7 Plus and a Leica 65mm APO Televid field scope. He contacted Eric Carpenter who relayed the news to the birding community.

Technical information

Model

COOLPIX P610

ISO

100

Focal length

197.1 mm

Flash

Flash did not fire, auto

f-stop

f/5.6

Shutter speed

1/500 sec

Dimensions

1440 pixels x 1080 pixels

Original file size

215.3 KB