Lesser Black-backed Gull

Blue ring with a white four alpha-numeric code, starting letter 'F', followed by a colon (:) and three alpha-numeric or numeric code (on left tarsus).

note 1 :  

Red ring with a white four alpha-numeric code, starting letter 'M' followed by a letter en two numbers.

note 1 :

Dark blue ring with white 3 alpha-numeric code : F/number/letter.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : used for adult birds from 1996 onwards.

note 3 : final letter  = A, B, C, D, E, H, J, K, L or M

note 4 : number = 0 - 9

note 5 : example codes are:  F1A, F9M etc

Dark blue ring with white 3 alpha-numeric code : number/number/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : 01F - 07F ringed in 1994, 08F - 9F ringed in 1995.

White ring with black 3 alpha-numeric code : number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 100 birds ringed in 2012.

note 3 : middle letter  = A, B, C, D, E, H, J, K, L or M.

note 4 : number = 0 - 9.

note 5 : example codes are:  2AF, 6EF, 9MF.

Light green ring with black 3 alpha-numeric code : number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 100 birds ringed in 2006.

note 3 : middle letter  = A, B, C, D, E, H, J, K, L or M.

note 4 : number = 0 - 9.

note 5 : example codes are:  2AF, 6EF, 9MF.

Orange ring with either green or black 3 alpha-numeric code, number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 200 birds ringed in 2001 and 2009

note 3 : middle letter  = A, B, C, D, E, H, J, K, L or M

note 4 : if characters are green then birds ringed in 2001, if black then 2009.

note 5 : number = 0 - 9.

note 6 : example codes are : 2AF, 6EF, 9MF

Red ring with white 3 alpha-numeric code : number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 200 birds ringed in 2002 and 2005

note 3 : if middle letter  = A, B, C, D, E, H, J, K, L or M then birds ringed in 2002

note 4 : if middle letter = N, P, S, T, U, V, W, X, Y or Z then birds ringed in 2005

note 5 : number = 0 - 9

note 6 : Example codes are:  2AF, 6EF, 9MF, 2XF, 5ZF

Yellow ring with black 3 alpha-numeric code : number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 200 birds ringed in 2000 and 2007.

note 3 : if middle letter  = A, B, C, D, E, H, J, K, L or M then birds ringed in 2000.

note 4 : if middle letter = N, P, S, T, U, V, W, X, Y or Z then birds ringed in 2007.

note 5 : number = 0 - 9.

note 6 : example codes are:  2AF, 6EF, 9MF, 2XF, 5ZF.

Dark Green ring with white 3 alpha-numeric code : number/letter/F.

note 1 : birds ringed at Flat Holm Island, Cardiff.

note 2 : about 200 birds ringed in 1999 and 2013.

note 3 : if middle letter  = A, B, C, D, E, H, J, K, L or M then birds ringed in 1999

note 4 : if middle letter = N, P, S, T, U, V, W, X, Y or Z then birds planned to be ringed in 2013.

note 5 : number = 0 - 9

note 6 : example codes are:  2AF, 6EF, 9MF, 2XF, 5ZF