onsdag 22. august 2012
Juv-1w caspian gull Fredrikstad
This nice caspian gull in almost full juvenile plumage suddenly appeared before me at Øra, Fredrikstad in the afternoon of monday 20th of august. I have been searching for one for years, so this was nice...
While first winter caspians are very contrasting and therefore easy to discover and straight forward to identify, juveniles are much more nondescript and requires a bit more attention to build and proportions. Roughly speaking, you take a herring gull and stretch and pull all extremities hard in all directions to get the caspian build. They are slimmer, longer winged, longer legged, longer billed and longer necked than an average herring gull, and it takes a very special herring gull indeed (probably in very bad health) to match one.
This bird is not entirely juvenile, though. It has renewed quite a few mantle feathers and scapulars, but these are rather diffusely patterned and do not contrast very much with the older, juvenile feathers.
I have added almost every photo (albeit of variable quality) I managed to get of the bird...Click for (slightly) larger version.
With two very different juv great black backed gulls...
Almost like a big-nosed phalarope when swimming on the water...
Lighter underwing than most herrings, but this individual is not extreme in this respect.
On last three pics: note again venetian blind effect and wing bar.
Next four pictures: Very typical slender body and "thumbnails "tertial markings
At rest a bit more squarish head shape.