Gulls

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

Yellow ring with black five alpha-numeric code, starting letter "S".

note 1 : after the letter can be letter or number.

note 2 : code to be read from bottom till top.

note 3 :

website sighting submit: 
European colour-ring Birding submit
email sighting submit: 
contactperson: 
Luka Jurinovic
colour-ring type: 
Legring : one, coded.
colour-ring colour (of the c-ring): 
Yellow [Y]
colour-ring code (of the c-ring): 
Five alpha-numeric code (5 letters/numbers).
countries where ringed: 
Croatia.
First letter/number (of the c-ring): 
S