Black-headed Gull
scientific name: 
Chroicocephalus ridibundus

Yellow ring with black four alpha-numeric code, starting letter 'E' and letter/number/number. 
also used : letter E + letter + letter + letter (EAAA-EZZZ).

note 1 : used codes are EA00-EZ99.

note 2 : used letters are A, E, H, J, K, L, M, N, P, R, S, T, U, V, X, Y.

note 3 : the project concerns breeding birds and pulli from a Belgian colony : for the 4 alpha-code >2500 birds ringed (dd. 04.2017) of which 1 hybrid ridibundus x melanochepalus and >3000 resightings.

note 4 : 

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