Gulls

species: 
Black-headed Gull
scientific name: 
Chroicocephalus ridibundus
notes: 

Black ring with a white four alpha-numeric code.

note 1 : starting letter "X" followed by three characters (letters/numbers).

note 2 : there are no codes in use that contain three numbers.

note 3 : some series show a small check-dot on different levels.

note 4 : c-rings are usually to be read from bottom to top.

note 5 : the metal ring can be attached to both the tibia and the tarsus.

note 6 : in use at different sites in eastern parts of Germany.

note 7 :

email sighting submit: 
colour-ring type: 
Legring : one, coded.
colour-ring colour (of the c-ring): 
Black (Niger) [N]
colour-ring code (of the c-ring): 
Four alpha-numeric code (4 letters/numbers).
countries where ringed: 
Germany.
Images: 
First letter/number (of the c-ring): 
X