Lesser Black-backed Gull

White ring with a black four alpha-numeric code, starting letter 'KJ' or 'KR' and two alpha-numerics. 

note 1 : 700 ringed in Russian Karelia during 2002-2008 ; some without  metal ring.

White ring witk a black four alpha-numeric code, starting letter 'M'.

note 1 : during the period 1995-2000 about 600 Lesser Black-backed Gulls (L.f.fuscus) were ringed.

White ring with a black four alpha-numeric code, starting letter 'A' followed 3 alpha-numerics.

note 1 : the metal BTO is fitted on the left leg.

note 2 : used codes are A1AA - A1ZZ black characters on white,  A2AA - A2ZZ black characters on white, A3AA - A3ZZ black characters on white, A4AA - A4ZZ black characters on white, A5AA - A5ZZ red characters on white, A6AA - A6zz black characters on white,  A7AA - A7ZZ black characters on white.

note 3 : codes will be used till A9**. The wild gull chicks have been ringed on roof nests along the south coast.

White ring with a black four alpha-numeric code :
* starting letter 'N' followed by a colon ":"
- followed by three numbers or three alpha-numerics. 
or
- followed by letter 'A' / number (4 or 5) / letter. 

note 1 : ex. : N:001-N:999 ; N:A4A ; N:A5X but also N:37X, ...

note 2 : 

White ring with a black four-alphanumeric code, starting letter 'N'.

note 1 : used codes are N500-N599.

note 2 : the project was running between 1995 and 2005, birds were ringed on a landfill site near Madrid and Badajoz.

White ring with a red six alpha-numeric code (Z, A or M and 4 alpha-numerics).

note 1 : used codes are ZA+4 digits for the Sisargas Islands (Malpica, A Coruña, Central Galica) and ZM+4 digits for the Sálvora Island (Ria de Arousa, South Galicia).

White ring with a black four alpha-numeric code.  

note 1 : used codes are N366 tot N399.

note 2 : birds are ringed during the winter at Tarragona Harbour.

Combination of a white ring with a red two alpha-numeric code (o nleft tibia) AND a black ring (on right tibia). 
Combination of a green ring with a white two alpha-numeric or alpha code (on left tibia) AND a black ring (on right tibia). 

note 1 : rings are 1,8cm. in height and re-placed above the knee (on the tibia) for better observation results in the colony (high vegetation) and on rubbish-dumps.

note 2 : 

White ring ring with a 2 alpha-numeric code code

note 1 : rings are placed above the knee (on the tibia) for better observation results in the colony (high vegetation) and on rubbish-dumps. All other colours (with vertical placed codes) above the knee are also part of this project.

note 2 : In some series  used dots (1.A), colons (1:A) or single or double bars (1|A or 1||A). Those additional marks are part of the code

note 3 : In some series is an additional plain marker present at the other tibia, this marker is part of the combination.

note 4: Same codes can be used by other large gull species. If you have doubts about the species and/or code, please note the age and position of all the rings, including the metal ring.

note 5: used letters/numers are : A, B, C, D, E, F, G, H, J, K, L, M, N, P, R, S, T, U, V, W, X, Y, Z, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, + and =. Only the letters I, O and Q are never used

note 6: In this project are also used a combination of two coloured rings with both one letter or number at each tibia.

White ring with a black 3 alpha-numeric code : “n.xn” , where n = number and x= a letter and “.” a dot.

note 1 : used codes are the letters T, U, V, and Z, and for 2008 the letter Z was used.

note 2 : birds are ringed at Bailiwick of Guernsey, Channel Islands.

note 3 : do please take notice of the “dot” as a check character.

note 4 : Annual Reports are available on the Guernsey Gulls web site (www.guernseygulls.co.uk) and also on the Guernsey Gulls Blogspot (www.guernseygulls.blogspot.com).

note 5 :