Gulls.

species: 
Lesser Black-backed Gull
scientific name: 
Larus fuscus
notes: 

White ring with a black four alpha-numeric code : number / number / letter 'Y' / number (on left leg) and metal ring (on right leg).

note 1 : used codes 00Y0 - 99Y9.

note 2 :

email sighting submit: 
website information: 
Gower Bird Hospital
colour-ring type: 
Legring : one, coded.
colour-ring colour (of the c-ring): 
White [W]
colour-ring code (of the c-ring): 
Four alpha-numeric code (4 letters/numbers).
colour-ring position (of the c-ring): 
Tarsus left.
countries where ringed: 
United Kingdom.