Gulls

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

Blue ring with a white four alpha-numeric code, starting letter "N" / number / number / letter "N".

note 1 : 

email sighting submit: 
email sighting submit (2): 
colour-ring type: 
Legring : one, coded.
colour-ring colour (of the c-ring): 
Dark Blue [B]
colour-ring code (of the c-ring): 
Four alpha-numeric code (4 letters/numbers).
countries where ringed: 
Spain.
First letter/number (of the c-ring): 
N
Last letter (of the c-ring): 
N