A Couple of Interesting Immature Yellow-legged Gulls

During my trip to Portugal in late September and early October I photographed a couple of immature colour-ringed Yellow-legged Gulls, which I identified correctly. However, I had a few lingering doubts. The first one was in juvenile plumage, which was unusual as all the other first year Yellow-legged Gulls had made good progress towards first-winter plumage. The fact that it had been taken into care might well be the reason for it still being in juvenile plumage as stressed birds often stall their moult. 

Juvenile Yellow-legged Gull

The other YLG's of a similar age had replaced most of their mantle and scapular feathers along with some of their coverts like the one in the photograph below:

First-winter Yellow-legged Gull

The other one (pictured below) was a second-winter bird and although its general character fits YLG, its plumage is not typical. It is much darker than I'd expect and it is very similar to the second-year Lesser Black-backed Gull behind it. The bill appears good for YLG as does the dark mask behind the eye and the large head size. It is resident in Portugal which helps point towards it being a YLG, as LBBG should move north in summer. It is healthy and able to fly as it moves along the coast between Portimao and Quarteira. Once again the plumage could be retarded due to the time it spent being rehabilitated. I might struggle with one like this if it turned up at Shawell.

Second-Year Yellow-legged Gull

Below is a more typical second-year YLG:

Second-year Yellow-legged Gull