below: 2cy Caspian Gull L-001754 (L. cachinnans), January 13-17 Lubna rubbish dump / Warschau, Poland (52.02N,20.50E).
This individual has replaced many feathers in the partial autumn moult (post-juvenile moult): The upper three tertials, the inner five and eighth greater coverts, all of the visible median coverts, the inner and central lower lesser coverts and a few lesser coverts have all been replace for second generation feathers. All scapulars, including the longest rear lower scapulars have been replaced for second generation feathers, and a new moult to third generation scapulars just started in the upper scapulars (which were previously replaced first in line). Note the strong neck-collar and division from the pale head.
We received data from Anatoly Poluda, of the Ukrainian Ringing Centre, B.Khmelnitsky Str 15, Kyiv-30, 01601, UKRAINE.
Kiev L-001754, Larus cachinnans. Ringed as pullus, 03.06.2003, Ukraine, Cherkassy O., Kanivska GES (49.46N, 31.28E)
below: 2cy Caspian Gull (L. cachinnans), mid-January 2004, Lubna rubbish dump / Warschau, Poland (52.02N,20.50E).
Nice example of cachinnans, with pale head and dark streaked "boa" in neck. Juvenile wing-coverts are still relatively dark brown, lacking the obvious wear and bleaching which is found in most first winter birds. No wing-coverts moulted.
below: Caspian Gull (Larus cachinnans) 2cy, July 17 2001, Huizen, the Netherlands.
This 2cy bird is typical in its cachinnans-like jizz, but the scapulars and coverts are extreme in their pattern for a cachinnans. However, they resemble the feather pattern as is found in the 2cy Kiev bird illustrated in picture 1.
When 2cy cachinnans moult the scapulars in the spring moult, the new feathers often appear pale greyish with a pronounced dark shaft streak. Upper-parts are often grey in 2cy by July, but in this individual, the scapulars show extensive dark centres. The supposed 3rd generation scapulars are very 2nd generation-like.
As can be seen in the picture, the inner two greater coverts and two upper tertials are missing and the entire median covert row has been shed. The lower lesser coverts are moulting to 3rd generation feathers.
The inner five primaries have paler inner webs and primary 7 is fully grown. The entire tail has been replaced recently.
Note the collar, typical for cachinnans.