Common Tern

Blue ring with a white three alpha-numeric code starting with an N, in combination with 2 numbers the N can be on the 2nd or 3rd position.

note 2 : the letter N is followed by one letter and one number (eg. NV2 or N2V) or by two letters (eg. NVN or NNV).  

note 3 : used letters are : A, C, F, H, K, L, N, P, R, S, T, V, X, Z. Used numbers are 1, 2, 3, 4, 5, 6, 7, 8, 9,0

note 4 : these codes were used from 2013 onwards on both adult and juvenile birds during the breeding season in the southwest of the Netherlands.

note 5 : a joint project of the Research Institute for Nature and Forest (INBO), Bureau Waardenburg and Ringgroup Delta.

note 6 : we use colour-rings to gain information on habitat use, juvenile dispersal, age of return and recruitment to the breeding colonies in the southwest of The Netherlands or beyond.

note 7 :

Blue ring with a white two numeric code.

note 1 : used numbers are 1, 2, 3, 4, 5, 6, 7, 8, 9.

note 2 : these codes were used in 2010-2013 on both adult and juvenile birds during the breeding season in the southwest of the Netherlands.

note 3 : a joint project of the Research Institute for Nature and Forest (INBO), Bureau Waardenburg and Ringgroup Delta.

note 4 : we use colour-rings in order to gain information on habitat use, juvenile dispersal, age of return and recruitment to the breeding colonies in the southwest of The Netherlands or beyond.

note 5 :

Blue legring with a white three alpha code (on tarsus left) and metal ring (on tarsus right).

note 1 : to be read from bottom till top.

note 2 :

Red ring with a white three numeric code.

note 1 : used codes: 0.00-0.99

note 2 : birds ringed in Staffordshire, UK.

note 3 : 

White flag with a black three alpha-numeric code.

note 1 : used letters as first letter : A, B, C, E, F ,H , J,K, L, M ,U, V, X, Y, Z.

note 2 :

Yellow ring with a black 3 alpha-numeric code : letter M followed by 2 numbers (on left leg) and metal ring (on right leg) OR number, letter M, number.

note 1 : birds ringed in Strathclyde Region, Scotland.

note 2 : used codes are M01-M99.

note 3 : 

Dark-blue ring with a white three alpha code, starting letter 'L or H' (on one leg) and metal ring (on other leg). 

note 1 : this project started in Northeast Germany in 2012. Until 2016 it was carried through with yellow rings with first letter 'F'.

note 2 : codes with second letter U, V, X and Z were used in southern part of East Germany (near city of Leipzig) in the years 2017 and 2018.

note 3 : from 2016, blue rings with the first letter being “H” have been used. Hence: blue “H” has been used from 2016 to 2019.

note 4 : 

White ring with a black three alpa-numeric code, starting letter "H", followed by a dot "." a letter and a number.

note 1 : used letters and numbers are : A, E, F, H, J, L, N, P, R, S, T, V, X, Z and 0 till 9.

note 2 :

Orange ring with a black 3 alpha-numeric code : letter U followed by 2 numbers (on left leg) and metal ring (on right leg).

note 1 : birds ringed in Leicestershire, UK.

note 2 : birds ringed during 2019.

note 3 : only used U00 to U17.

note 4 :

Orange ring with a a black three alphanumeric code (two numerics and letter K that might be on positions: nKn, nnK, where "n" is a digit 0-9) (on left leg) and metal ring (on right leg).

note 1 : used codes are :
K01-K16  (stop using)
0K0- 9K9
00K-99K

note 2 :