Sunday, October 25, 2009

L.smithsonianus(?) in Beppu

This bird showed up among the flock of Vega and Taimyr Gulls at the beach last Sunday, October 18. It has pale grey upperparts, remarkably paler than Vega Gulls, quite fit to the American Herring Gull(Larus smithsonianus). The grey tone also looks more bluish-tinge than Vega and Taimyr too. The bird seems to be in its first alternative plumage since there's not so many streaking on its head. Black markings on primaries stop at p5. Its p8-9 and greater coverts are still juvenile feathers and its bill still has some small blackish markings on both mandibles. Its P10 & P7 are growing.

With a Taimyr Gull in the front. The bird still has black marks on its tail feathers.

Comparing to the Vega Gull on the left, its grey part looks paler with more bluish-tinge.

But they didn't seem to get along very well.

Then it landed nearby.

With a rather small Taimyr Gull on the left

Comparing to the Vega Gull(below) in the same posture and lighting direction.

Since the bird is not yet a full adult, the color of the orbital ring is not clearly defined, but definitely not red.

With the same smallish Taimyr Gull on the left. It was getting dark, yet the difference of the grey shade on the back can still be evident.

The greyish part can easily be distorted by the angle of the bird's body. The mantle of the Vega Gull in the middle looks pale because it's standing in the right angle, while the others' mantle just look totally different. This condition of light is not good for gull watching so I decided to go back to my room.


S.C.E. said...

You've got your East Asian Gulls well and truly sorted.........

Russell Jenkins said...

Some wonderful photographs and good ID work. I've been seeing plenty of gulls too but still haven't worked out what they are. Every year is the same. -I try to learn about them but I quickly forget what I learn anyway. Nice work.