Gulls

species: 
Great Black-backed Gull
scientific name: 
Larus marinus
notes: 

Orange ring with a black code three alpha-numeric code (starting letter B ”, followed colon ":" and two numbers).

note 1 : two birds ringed with an orange ring with a four alpha-numeric code.

note 2 :

website sighting submit: 
Aranzadi Portal for special marks in birds.
email sighting submit: 
colour-ring type: 
Legring : one, coded.
colour-ring colour (of the c-ring): 
Orange [O]
colour-ring code (of the c-ring): 
Three alpha-numeric code (3 letters/numbers).
colour-ring position (of the c-ring): 
Tarsus right.
countries where ringed: 
Spain.
First letter/number (of the c-ring): 
B